Indeed, the eZ80 not only continues the instruction set (with 24 bit extensions no less) but does so at 50 MHz clock speeds. Can you imagine whan an Amstrad CPC would have been like with a 50MHz Z80?:) Fun part being that you could almost certainly STILL run CP/M on the eZ80. :)
The good part with the eZ80 is not only it's speed, but also that it's a quite energy efficient chip, the 50Mhz chip can run code as fast as a 150 Mhz Z80. By the way, the video didn't even mentioned the major reason many computer producers especially in the 1980s preferred the Z80 over the 8080: You ONLY needed a single 5V+ line, the 8080 needed 5V+, 5V- and 12V+, which meant you needed THREE discrete electrical circuits to run the chip. That's the reason why the Z80 fits into small calculators or handhelds and can run off four parallel 1,5V batteries or ONE 9V battery block. And why it can be used as an easy microcontroller, in space etc
@@acmenipponair Exactly, that's why I loved it, too. Around 1983 I then switched to Z180 when my products needed more memory. It was such a joy to work with, I wrote tens of thousands lines of assembly language code for it; I doubt modern day designers can experience such an intimate closeness to the machine. 🙂
Reminded of writing Z80 hex for a Spectrum into the wee hours. I was 20, working unskilled jobs, knew nothing. BASIC was okay for programming concepts but it gave little idea of what was actually happening and I needed that. Things started to click when I realised video was just part of the memory. First tools I wrote were an assembler and a text editor, it didn’t really occur to me these would already be available. Then discovered C and compilers. I think, without that grounding I’d have not ended up working in IT. Thank you Sir Clive.
Z80 had a great run. Back in late 80s it was the first CPU I programmed directly in machine instruction code (yes, converting instructions into hex numbers, calculating relative offsets).
Reminds me of my days as a Technician who inherited a microcontroller design from a departed engineer. It was 68HC11 based with a UV EPROM for code execution. My tools were a text editor (B) and the motorola AS11 assembler with debug done with a logic analyzer. Burn & Crash FTW. I hated waiting on the UV eraser box.
@@thudtheace Acorn originally adopted the 6502. Then they developed their own chip called ARM, which is very definitely the winner in terms of volume shipped.
@@katrinabryce Here you are wrong. Because ARM is NOT a chip - it's an architecture. There are many many many different chips using different ARM versions, but the original chip only was produced for some years. The 6502 is a literal chip that is produced until this day. So when it comes to the chip war, the 6502 has won. When you would compare architectures, then the x86 is still the winner, as any chip produced by Intel or AMD at the moment is based on the x86 architecture, just much more modern.
I still have my Timex Sinclair 1000 in storage. It was my first computer and introduced me to the field. I've recently retired as a Network Administrator after a long IT career, all because of that Z80.
I started with the Timex Sinclair 1000 back around 82-83 maybe? Learned the little simple basic they had at the time, and eventually how lacking it _could be at times_ , so we moved right into poking code directly into memory. Loved playing around with that thing... even remember seeing an article for a voice recognition program (since you could use the MIC in/out ports normally reserved for saving and loading programs).... I've been a tinkerer ever since then, with only a short break due to my first marriage. Should have just stayed in playing on the Sinclair in retrospect! At any rate, kind of the same story. Once I got back into things, Windows had came along and progressed fairly well. I've been playing catch ever since. However, I'm now at the point where I have completely left having to go out to work, and do everything from a little home office now as well. That little Sinclair was some great times and good memories, and undoubtedly led to many many individuals making everything run today! I just didn't realize how many things the Z80 was actually in...!!
Many years ago I had a Heathkit H89 computer which used two Z80 cpus. One of the Z80s was on the main computer board, the other Z80 was on the video terminal board. This computer could run two operating systems. One of the operating systems was Heath Disk Operating System, known as HDOS. The other operating system was CP/M.
It could also run UCSD pascal, which was its own operating system with a p-code interpreter integrated into the p-System (the name given to the operating system). Capable of concurrent multitasking at a time when MS-DOS was strictly single thread. The performance of the H89 was, for the day, remarkably good. We used one in conjunction with an external box, to emulate a wide range of CPU's in hardware and driver development. Ultimately UCSD priced itself out of the market.
There was another version of this computer. The kit form was called the Heathkit H89, the fully assembled version was marketed under the Zenith Data Systems name as the Zenith Data Systems H90. It is too bad the Heathkit and Zenith Data Systems went out of business.
@@davidgapp1457 It''s a shame because the p-system is inherently portable and could easily adapt to new cpus. SofTech dropped the product, and it was picked up by Pecan Systems, owned and run by real enthusiast users. But the market at the time wanted to coalesce around a single OS, just about any microcomputer OS might have been embraced, but IBM PC-DOS and MS-DOSes turned out to be that, although early MS-DOSes, were really a bunch of incompatible OSes. Compaq, Phoenix and the other clone makers fixed that.
I am surpried that no credit is given to Ted Hoff (Intel employee No.12). Hoff came up with the idea of using a "universal self-contained processor" rather than a collection of discreet chips. He designed the instruction set for the Intel 4004 with Stanley Mazor in 1969. Development of the actual 4004 chip was done by Federico Faggin, as mentioned. They are all credited with the invention of the Microprocessor.
I'm from Germany and bought a TRS80 Level-II compatible computer in 1982 or so, which I still have and it's still running. I expanded the memory from 16kByte to 32kByte using a piggyback memory chip. Back then, for lack of opportunity, I learned the Z80 mnemonic (load register, shifting, ...) and programmed the TRS80 directly. What a fun time. Used my cassette deck as a storage device - I didn't have enough money for a floppy disk drive. Didn't know the Z80 has been in production since 2024. Thanks for your video.
Thank you for this respectful homage to a great idea; regardless of the z80 being their peak or not - It is most definitely valid to say that we owe Zilog a lot!
I found this video fascinating and sad in some ways seeing at the same time seeing an old acquaintance retire but then again technology moves on. From 1980 to 1987, I worked for Visual Technology. Visual used the Z80 almost exclusively in their terminal products except for one model that came out in early 1987 which used the 68K. In addition to their terminals, they also produced a couple of personal computers, with one being the V1050. The V1050 had both a Z80 for its main operations and a 6502 for graphics allowing the system to perform some amazing tasks and ran CP/M Plus. As a technician, I knew the pinouts inside and out and while attending night classes towards my degree, I took a class in Z80 Assembly language which was offered at the time. As it turned out, the professor owned a Visual V1050 and I ended up repairing it for him when it crashed. For our class project, we used Apple II computers with that Z80 card installed. All it took was a simple key-combination that switched between Apple OS and CP/M 2.0.
I had a TRS-80 and often used EDASM (an editor and assembler). You could do nice things with the memory-mapped display. One thing I remember was a 3D game-of-life program I wrote in assembly. At the time you could really fully understand a PC. I soldered another 3 sets of memory on top of the 16 KB RAM and added an address decoder to create a whopping 48 kByte RAM. Also a lower-case character generator as the base TRS-80 only had CAPITALS...
I did quite a lot of 'upgrades' for the TRS-80 screen memory, but it only took a single 1k x 1bit SRAM chip (from memory a 2102 or something like that) piggybacked on one of the already installed SRAMs with the chip select line taken off to pick up from the main RAM. I used to additionally put a toggle switch between two of the ports on the back plain that could turn the chip enable on and off due to many of the PROM masks being wrongly written. I did all my early programming by hand assembly and then typing in the hex-code using T-BUG. 😁
What an awesome video essay! I'm 50 years old, & am fully conscious of the wonder, magic & marvel of where we are today. When I'm at my computer - I'm aware of the entire history that got us to this point - & that I get to interact with this technology, just like that. At school - we had the Tandy green-font computers, & later on in Secondary school (c. 1982+) - the BBC Micro. Plus some Apples - which were in the 'graphics' department.
This is a brilliant documentary. Just to add, $26 in 1976 was roughly half a week wages in a ordinary job today. By ordinary, I mean somewhere between a retail worker or delivery driver. I still believe in the Z80
Thanks very much for your kind words! It was still a decent chunk of change, but certainly affordable compared to the thousands of bucks Intel would charge. Only after the success of the 6502 and Z80 did Intel & Motorola see that computers could be in every home and office and started to scale their prices accordingly
Cheer up, this is not an end of an era yet. Z80 is dead but eZ80 still lives on. Same instructions, better chip. And some small Chinese company might still pick it up anyway.
Wouldn't be too concerned. There are millions of Z80 based chips out there - including SoC versions of the Z80. In addition, you can emulate the Z80 in a FPGA (or similar) which yields a performance considerably superior to the stock chip. Personally, I bought one of the Spectrum Next Edition 2 which took me straight back to my first computer!
@@davidgapp1457 I'd think some foundry in China would just re-silicon-compile the Z80 into a modern process and continue manufacturing.. Likely get a must faster version of the part as well.
well, for that matter the GameBoy and probably others, are "Z80-derived" and not actually Zilog's chip. TI83 series also had Z80, and if you want to get really pedantic, the "TI84 series" is always referred to as the "TI84-Plus" series, in Texas Instruments documentation.The 83 got an upgrade to "Plus" and they kept "Plus" in the names of all the TI84s.
@@edwardteller5879 TI-81 to T!-86 used Z80, and so did TI-73. The earlier TI-80 used some weird Toshiba thing. TI-89, TI-92 and TI Voyage 200 used 68000.
@@ijabbott63 you forgot the T83 series and TI84-Plus series, unless I am misinformed. The first TI-80 Pocket Computer used two 4004s. Not in any sort of "dual core" set up or the equivalent, Sharp (these were re-branded by TI) just divided CPU functions between the two. This is the kind of fact that AI hallucinates on, I'm sure confusing The Pocket Computer with the other TI-80 microcomputer line. The Pocket Computer heavily marketed on it's ability to do BASIC, which at the time made it not a calculator, at least according to TI marketing and their literature, anyways.
@@squirlmy I was including the TI-83 and TI-84 series within "TI-81 to TI-86", also including the TI-82 series and TI-85. I was mistaken about TI's first graphing calculator was the TI-81, not the TI-80. The TI-80 graphing calculator came several years after the TI-81 and was unusual in not using a Z80. I think you were thinking of the TRS-80 pocket computer.
I still have a Z80-powered clock, built from a kit. It picked up the 60KHz radio signal from Rubgy, UK. The signal contained the date and time from an atomic clock, and was sent as a fast data burst in the first second of every minute for equipment capable of reading it, followed by the same information transmitted as pulses at 1 second intervals for slower eqipment. It has no RAM, just an EEPROM with the code and a bunch of chips to drive a 6-digit 7-segment display. It's called the REWBICHRON, published in Radio & Electronics World back in the 80's.
Our company used the Z-80 as our workhorse in the early 80's. We used it for many of our embedded systems in prototype inspection equipment. A group of us created a transportable robot to solve the Rubik's Cube in 1982 and even published some papers on it. Such great memories!
I really loved the assembly language mnemonics of the Z80, as it was so much better than those of the 8080. My first real computer after my Apple II was a Columbia Data Products 964 Commander running CP/M, with dual Z80s and dual banks of 64k ram. It was essentially two computers connected with an internal serial interface, where one system was responsible for screen output, and the other for running applications. I even had an arithmetic co-processor to handle trigonometric functions. There were no built-in functions to draw a line or shade a polygon, so I had to write my own in assembly language. I paid $4000 for it around 1979 (a huge sum of money) and developed a 3D solid modeling application in FORTRAN which I sold for $17,500 a year later.
I loved the Z80 and used it for real time industrial controllers. It had two separate sets of hardware context (registers and the like) So I kept the real time stuff in one context and the non time critical stuff in the other context. This allowed me to take a timed synced interrupt, and do my real time work without have to push and pop registers to the stack. I used the other context for supervisory work like a console, reading buttons, printing reports and maintaining production logs. Now I am amazed with what I could to with 16 kb of rom and maybe 4 of ram.
@@AlsGeekLabthe Z80 CPU was a good system to use, but it was only 48 Years of age when it had suddenly failed in 2024, after it was completed in 1976.
This video just reminded me that I have a Z80 kit which needs debugging. In the early 80s I worked in distribution and we sold the Mostek MK3880 and the NSC800 the first CMOS Z80/8085 clone (but not pin compatible). I worked as a programmer with the huge (the aircraft carrier) Hitachi HD64180. To this day I can take a hex dump and disassemble it in my head.
TRS-80 Model I / III were the first two computers I programmed on in the early 80s at school. Our family's first computer was a Kaypro II in early 1984. All of these beauties powered by the Zilog Z80.
I put together a TRS-80 with the Z-80 and I used that thick book which had the instruction set in it( I threw it away and I wish I hadn't) to do all sorts of things in assembly. This was in 1979 I guess. Because I had done Fourier Theory a few years earlier I actually did an FFT in assembly and finally got it to work. The file was on a cassette. I never did programming as a career as I was more an applied mathematician. Years later when I was doing the Giant Mersenne Prime Number Search I came across a programmer who had programmed an FFT for the large number multiplication used in that application. It brought back memories of the Z-80.
Was a 6502 kid myself. had some neat tricks of it's own with zero page address redirection saving many cycles to perform similar... also able to rewrite it's own code because of the shared memory space.
Don't get me wrong the Z80 was a beast... but I had to make do with what I had ;) The real issue was that neither Zilog or Rockwell were quick on the uptake of SOC so most of the first generation of embedded's ended up being 8088/6 devices. Dallas Semi took those and ran making some really cool ultra low powered devices with some exceptional low power static ram stuff based off of the 8051 architecture.
6502 at home, 8080 in school. Both had easy to learn layout and instruction set. I preferred 6502 because of addressing modes, but had nothing against 8080.
I learned about microprocessors via the Z80 and building my own Z80 based microcomputer as a lab project in college. That knowledge has stood me in good stead bringing many Z80 things back to life, both in industry as well as electronic music instruments* for hobbyists. (*): extensively used in those as well, with some frightening shortcuts taken in terms of digital design, to where I sometimes wondered how they ever worked at all. But: replace the faulty component (in 30+ years I've only seen 1 actually faulty Z80 CPU) and these things just spring to life again. A remarkably robust and forgiving design.
I still have fine memories about Borland Turbo Pascal, the integrated compiler debugger compiler for pascal. Great for quickly writing engineering software.
Made a project when i was in the sixth form (1980-81) - disco light sequencer built around a Z80A. Hand compiled assembler into a 2716 UV EPROM. Hand drawn photo etched PCB. It eventually died when the NiCd battery leaked and ate the track!
My first computer in 1982 was a used TRS-80 Model III, with a cassette as it had no floppy or hard drives. The programming foundation I got then from still serves me today.
A small addition to your fine video. The Intel 4004 was widely used as a traffic light controller. I too owned a TRS-80 in 1980. The most interesting Z80B fact that I can add is I remember seeing a Z80B chip used on a Parallel Interface Card built for the ISA bus on a PC. The CPU that ran the whole computer was now relegated to running the printer interface. One hell of a printer card if you ask me!
Back in 1978, when I was eighteen, I bought one Z80, along with eight 1Kb DRAM chips (which were more expensive than the processor itself), and I tried to create my own personal computer, using NASA"s apollo 11 wrapping technique for the wiring. That was five years before Apple II... I even hand-coded a BASIC interpreter in Z80 assembly langage. The Zilog Z80 was so much more cool and powerful than its closest competitor, the Motorola 6502! Its instruction set was so clever! Later, I had a TRS-80, then a Sinclair QL (wich has a 68008 processor, another landmark in the area of microprocessors), and an Atari 1024ST... But I will never forget the Z80. RIP!
Back in my 6502 days I rewrote lots of code from Z80 to 6502 or more rarely, a high level programming language. I perceived the 6502 as minimalistic, the Z80 as pretty quirky, borderline ugly. My next major architecture was the 68000, 68010, 68020, 68881/68882, 68851, 68030. Simpler to the programmer but bloated. The move instruction timing was so complicated for the 68020 that the timing tables covered a double page in the manual. For the 68851 tables became so hopeless that the appendix of the manual contained huge bash scripts to compute execution times. Makes your head spin. SPARC was weird with its register windows - I didn't like them even when I first read about the in spring of '88. At the same time I read about MIPS for the first time and perceived it as painfully simplistic. It wasn't always obvious how to do some stuff. Some of the stuff took a while to wrap my head around but I eventually became a MIPS guru. Then my IA-64 intermezzo - the philosophy of it never made sense to me. Finally RISC-V which with my MIPS background is a bit like MIPS stirred up, thrown into the air and what falls down is RISC-V. Just kidding. More realistically I'd describe it as RRISC or Reduced RISC. Thinks that even the RISC designers in the 80s didn't dare to remove the RISC-V designers did. Along the way some Alpha. Nice design but sadly primary going fast due to the insane clockrate - one of the technical aspects (think heat) limiting its market success.
The 8008 was my first venture into micros from a mainframe background. It really took off with a Nascom Z80 kit for which I designed several addon cards as well as embedded systems. The 286 was a step change though, and I still remember prototyping my own designed production motherboard using the Chips and Technology chipset using wirewrap 😁 before going to PCB. Huge progress since in both SoCs for embedded systems all the way up to my current OC'd 14900KS monster. Memories ❤.
Except the Z80 only has a 4-bit ALU and lots of its instructions are on one end of the clock tick. The 6502 has a true 8-bit ALU and it can process instructions on the top and bottom of the clock tick. If both at 1MHz, the 6502 far outperforms the Z80. That's the key isn't it, the Z80 was usually at 3.25MHz, 4MHz or some faster speed, so the Z80 seems better at first.
Yes I think that's why I said that the 6502 was better on paper. The Z80 outperformed it because it was provided at greater clock speeds than the 6502 at the time
and again the same stupid mhx comparison which does not mean nothing. a 6502 @4Mhz require so much DRAM speed that with the same memory chips you can interface a 16Mhz Z80! so the ratio is the same. the apparent efficiency on 6502 is due to the double clock usage while the z80 use a faster single clock and divide by 2 or more the clock to perform its internal operation while the 6502 used the clock "as is". What does matter is the amount of operations a processor can do at maximum clock rate, not the maximum clock rate itself. On this side a z80 CPU outperform the 6502 by 20% to more than 200%! look for example a full range LDIR instruction which does memory move operations. The 6502 didn't have this instruction and emulating this via code is itselft 3-4 time slower even at same clock rate. OF course this is a extreme comparison and choosing some use cases one can show that the 6502 could be faster than z80 (for example emulating a pre or post indexed memory operations), but in real world scenario one can expect the z80 to be at least 20% faster if both processors were clocked at maximum clock rate. And i was comparing the original versions of both cpus not some enhancements. The main limit on 6502 is the absence of gen purpose registers ( well, we have register A, X, Y ) which forced a more intensive memory based operations where the z80 could operate internally on registers.
I’ve posted this comment on other videos, but… oh well! My first computer was an Exidy Sorcerer. It had a Z 80 processor, but I’m not sure about the speed. A broken center lead on a big transistor in the power supply caused it to die an untimely death. I still miss it. It was a fun machine, and I learned to program first in BASIC, then assembly language on it. Later on, I was able to use that knowledge to program in assembly language on the IBM 370 and beyond.
My first Z80 based computer was a North Star Horizon, ordered in 1979 and put into commercial use in 1980. 32Mb of RAM and dual floppy disk drives, double sided. Ran North Star OS. Later upgraded to 64Mb to run CP/M.
You surely mean kB, not MB - the Z80 has a 16bit address bus. All it can use without bank switching are a maximimum of 64 kB of RAM+ROM storage. Also 32MB of RAM in 1979 would have been prohibitively expensive.
I learned to use the computer on a machine with Z80A and 64 Kb RAM...it ran CP/M 3.1 on it and brought with it an overwhelming amount of software. In the years between 1983 and 1985 I learned to use C, Macroassembler Z80, DBase, COBOL, Basic (two or three dialects), all stored on big 8-inch floppy disks (and 1.2 Mb capacity). It seems like yesterday, but forty years have passed. Still, the wonder that chip had aroused in me I will never forget: heartfelt thanks to my fellow countryman Federico Faggin for all that...
in the U.K. I built a nascom 1 and 2 from kits in the late 1970s soldering the components to the pcbs and learnt to program on them, Z80 assembly code and tiny basic , I owe so much of early career to the Z80 thank you for the video. Future generations should be thankful to such brilliant minds that have given us the modern technology all take for granted.
The Z80 is my favorite CPU alongg with the 6502. I've always wondered how fast they could be if more modern processes were used to make them, say 90nm or something. Of course the die would be so small that a very accurate tiny robot would have to package it, but they could get millions from a wafer.
They could indeed be wicked fast, but without intermediate internal cache augmentation or simply incorporating all system memory on-chip (yesterday’s system memory size is today’s cache size), it would spend vastly more time in wait state’s than execution.
I was born the same year as Unix, about the same time as the equivalent of Unix 1.0. To really geek out, my birthday in Unix Time is in the low millions, but saying this doesn't make me very popular at parties for some reason
My first system, and first assembly I learned. A rare 'Exidy Sorcerer' with rom cartridges and Kansas-City tape interface. Ahh... those were the heady days of user groups meeting in person to exchange cassette tapes of programs we'd spent hours typing in. :)
My first computer was a Cromemco Z80 system on an S100 bus, with 64K RAM and two 241K 8" floppy disks running CDOS, a CP/M clone. Later I upgraded to a (massive!) 10MB hard disk, and recoded the OS to support it - not too hard in those days, with just serial port and two disk drivers needed. That computer did a lot of work for me. Simpler times indeed!
That would have been a really cool experience! If you'd ever feel like having a chat about your machine on the channel, I think that would make a great story! Drop me a line if you would like that!
I built a Cromemco Z1 kit for my college in 1978. Like your machine, ours had 64K RAM and two floppy drives. We used the machine in our computer science classes to study operating system design as our IBM Remote Job Entry system into an IBM 370 limited our ability to get down to the hardware level and write device drivers. Upon graduation in 1980, I joined Mostek and became a factory application engineer on the STD bus which was based on the Z80 chip family
In 1972 Rockwell released a 4 bit CPU that consisted of a three chip set. My first job as an electronics engineer was with a company that produced a product call a 'computing integrator' which was used in conjunction with chemical analyst instruments. The first gen used discrete ICs. 2nd gen used the Rockwell set. Third gen was Intel 8008, followed by the 8080, and then the Zilog Z80.
Still (as a Brit) struggling to come to terms with someone with a Scottish accent refering to this chip as a ZEE Eighty. I've always called it the ZED Eighty. I first started to use and program this device in 1979 using a Zilog MCZ-20 development machine using the RIO operating system. That's it at 1:09 (the blue box with the cream lid) and I wish I'd kept this machine instead of putting it in a skip all those years ago.
I literally had to write zee 80 in my script to say it that way. It was an American product so it's called a zee 80 by Zilog so it is only right to call it Zee-80. In my head I was screaming every time I said it though!
The Z-80 family was the first processor I learned to create systems with: both hardware and low-level firmware coding. I keep a warm memory of those times 🙂
I am fortunate to have worked with the entire Z80 family to the point of memorizing their pinouts and the CPU instructions, being able to write assembly code and immediately translate to the opcodes. Fun times indeed but sad as it is the end of Z80 production, progress always moves forward.
My first interview to be a professional programmer after finishing college here in Ireland was to be a Z80 programmer for embedded telecoms units for Motorola. That was 1998. I was shocked/surprised that the processor that I knew from old home computers was being used to run mobile networks! In hindsight, I ought not have been. Was a great implementation. I didn't take the job. Went and used this new language my buddy told me to learn for my final year project - Java. Ended up going enterprise, baby! 😕 Feel lucky to have found this a few days after the Zilog announcement. Are there any other late-70's "mass market" chips still in production now? Winners and losers in the high-stakes game of early tech adopters... It's an enthralling set of stories. "Gary Kildall's CP/M" - I'm glad you called it that each time. Thanks for this, I love this class of content. Subbed 👍
My father bought a TRS-80 Model I, when they first came out. We had it at home for quite a while and he and I taught ourselves to work it and do some 'BASIC' programming. They didn't really have computer courses at colleges and universities back then, you had to teach yourself. Later on we (Dad's office) had the TRS-80 Model II, and then went to the TRS-80 Model 2000. This was all BMS (Before MicroSoft) ... Jobs and Wozniak were busy tinkering around in their garage creating Apple computers. I did a course at college one time as a 'mature' student, and most of the students were fresh out of high school. I don't think any of them believed that there were computers around before the IBM PC and Microsoft WIndows ... etc.
Z80 was the first CPU that I worked on..as a college group project... was able to have that project successfully running on breadboard... to the delight of my professors that time... our group passed that course...
Back in 1994, I have built a very simple development system based on a Z80, as part of my robotics diploma project at BCIT. A single-sided PCB for processor and memory, point to point wiring on a perfboard for IO. Four-digit LED hex display with a 16-key keypad for program input. Program storage on an UV erasable EPROM. The idea was to servo control a motor. It was certainly more fun and educational than buying an off the shelf "student" system. It's surprising to hear that this ancient architecture is still in use.
The early 80s also saw a Z80 clone, called the U880, that was one of the most widely used chips in the eastern bloc. One of these powered my first home computer (KC85).
@@thanatosor Hot enough that you would need active cooling. The PDIP-40 can run up to 14 MHz without additional cooling according to the data sheet but nothing stops you to clock it higher. Well, the capacitance of the PDIP-40 will eventually get in the way. But there are PLCC-44 variants which can go further. Provided you add sufficient active cooling. You should not do any of that for production environments of corse.
Various sources, I don't have the script with me right now and I made the video over two months ago (it's been up on my Patreon channel a while). I believe some of it was Intel archives, computer museum, excerpts from interviews from Faggin and also Wikipedia where I could cross-check.
Do you typically not post them or will they be appearing later? I wrote a piece on the same subject and would be keen to expand on my piece with some of the other things you mentioned here. 😊
Back in the day I made an adapter card with an NSC800 (CMOS with Z80 instruction set) for my IMSAI 8080. To match the 8080 pinout and ROM timing a few inverters and bit of logic to add a wait state were needed. But it doubled the CPU speed and expanded the instruction set. Those were the days.
@@AlsGeekLab The original NSC800 was a drop in replacement. Then the lawyers got involved. They had to make it incompatible. I just unincompatibleized it... well, and added a wait state in the ROM address space. The last thing I designed was a 10kV 5A power supply for the power oscillator (a water cooled tube) of a cyclotron. Why a tube? It lives in a high radiation area where solid state stuff goes to die.
I didn't know the Z80 was still in use until recently. I have an Osborne 1 in my attic, learned a lot from it. It got me started on a 40+ year career in IT. Now I'm mostly retired.
It’s in the Mega Drive/Genesis as well. Along side the Motorola chip. It handles the sound and since it’s the heart of the Master System also handles the backwards compatibility. It’s truly a legendary chip.
The Z80, the Sinclair Spectrum, the Commodore 64, and all the people behind them… Thank you 🫡 These products and people, even the ones writing those zany gaming magazines of the 1980s/90s, defined my life and made the world a much happier place! 🤍
"Gary Kildall: The man that could have been Bill Gates" I can't help but think that the world would be a much better place if that had been the outcome in this timeline...
The shop I worked in (1976-80)sold the Exidy Sorcerer, a Z80 micro, around 1977/8. Not a bad computer, it had 16 or 32k of RAM, could load and save to casette and you could plug in ROM modules (a PCB inside an 8-track cartridge!) for word processing or BASIC programming; other applications were planned but I never saw one. Then it got a disk drive unit that took 100k floppies or even a little hard disk, but that loaded MSDOS instead of the cartridges and took almost all of the working memory, leaving about 1.5k. I did write a stock control system to fit, but I had to use random access files on the floppy, making it slow. Museum piece now, of course. A few years ago, I threw out my Jupiter Ace, another Z80 machine, on the lines of the Sinclair ZX80, running Forth. I now find that they change hands for hundreds of pounds. Some you win... And, Al, why are you saying Z the American way? Makes the video annoying. Very annoying.
I have to wonder why the production was stopped. Change for the sake of change isn't usually good..... Very informative upload, great job ! I learned something here today, and I thank you, sir.
I'm surprised that Zilog never went after the potential performance benefits of switching for a full sized 8 bit ALU to the Z80. I guess while it would still be instruction-compatible, the timings would change, which could affect certain applications of the chips that had code reliant on many clock ticks each instruction used.
The Z80 was the second CPU I learned to program on back in the late 70's. The other was the 6502. After going through TRS-DOS and CP/M on my TRS-80 Model 4P, I didn't see the Z80 again until 2012. I got hired at a low-energy lighting company that used PCM to send current down a CAT-5 cable to effectively bit-bang a Z80 into powering LED lighting fixtures. The BOM on the Z80 made me laugh: the Z80 was a show-changer in its day, set my career going, and then heading into my final lap, I got to work with it again on a product that conserved significant energy, and did lots of cool stuff like follow-the-walker lighting. The unit had the Z80, the light, and multiple movement and temperature sensors. Brought joy to my heart to hook up a JTAG and reprogram it with my latest firmware install. Sorry to see the Z80 go. It served me well.
Absolutely SUPERB vId. The Z80 is dead, long live the Z80. Now for memory only ( no pun ) 21 LD HL 3E LD A. .... I have to stop, the wonderful memories of this chip planted in a Trash 80 was jut the ultimate for hardware / software playtime. Thks again for a great history vid, there are a good few things I did not know here even after all these years. Very well done sir.
I just got ahold of my childhood TI-84. While not from the era where the Z80 was a power house, it makes me want to finally take a dive at assembly and see what I can do with it.
The dear old Z80. The most important and certainly the most creative and fun part of my entire career as an electronics engineer was designing circuit boards, writing assembly language programs and inventing rather elaborate data acquisition systems, many of them using the STD bus and all based on the Z80. I was the company's microprocessor 'guru' and had my own lab. In my lab, I had a powerful advanced microprocessor development system designed especially for the Z80. Using the development system, I could compose assembly language programs, burn them into UVPROMS and then use the system's powerful emulator to debug the resulting system. With as little as 1K (as in 1000) of 8 bit bites, my little boards could sing and talk back to you and tell you what was going on inside complex systems, machine instructions burned into a PROM were that efficient. One of my boards that put out a whole range of phase variable test signals for testing Atlas rocket servo systems had no external RAM, but relied on juggling variables in the many registers in the Z80. This specialized waveform generator replaced a wonderfully complex (and rather brilliant) electromechanical system that used a rotary core 400 Hz transformer and very elaborate mechanical relay logic (originally designed in the early 1950's) that took up a whole cabinet (the 380 cabinet) whereas my Z80 equivalent was on a single 4X6 inch board. The other engineers wrote their test procedures and other work out by hand on paper tablets and then gave it to one of our secretaries to type up, but not me. I used the development system's editor to type up my own work myself and then I'd print it out on a large professional dot matrix printer. Those were wonderful and heady days and looking back today, I feel privileged to have been able to experience them. All this was thanks to the dear old Z80. By the way, I still have my TRS-80 that I used to teach myself assembly language programming before I got the professional development system.
programmed both the z80 and 6502 in assembly. Both great chips. But at the same clock speeds, the 6502A much faster at everything not needing 16 bit indexing. Primarily due to it's use of s-ram instead of dram and it's zero page addressing mode. I haven't got the manuals any longer so don't sue me here. But I think for example the z80 DJNZ instruction was 7T states, where as DEC xeroPage and BEQ were only 6T on the 6502. Either way though, both great chips... thanks for the trip down memory lane.
i've learned soldering with the z80. the ndr-klein computer was a modular selfbuilt system. one could build a full system from the scratch. i bought the empty boards and books (that's what i could afford) but had good connections for the chips.
Don't cry boys. Z80 is dead but Z180 and eZ80 still live on. Don't throw out your source codes yet.
Indeed, the eZ80 not only continues the instruction set (with 24 bit extensions no less) but does so at 50 MHz clock speeds.
Can you imagine whan an Amstrad CPC would have been like with a 50MHz Z80?:)
Fun part being that you could almost certainly STILL run CP/M on the eZ80. :)
Glad to hear about the eZ80 because the Olimex AgonLight2 uses it.
The good part with the eZ80 is not only it's speed, but also that it's a quite energy efficient chip, the 50Mhz chip can run code as fast as a 150 Mhz Z80.
By the way, the video didn't even mentioned the major reason many computer producers especially in the 1980s preferred the Z80 over the 8080: You ONLY needed a single 5V+ line, the 8080 needed 5V+, 5V- and 12V+, which meant you needed THREE discrete electrical circuits to run the chip. That's the reason why the Z80 fits into small calculators or handhelds and can run off four parallel 1,5V batteries or ONE 9V battery block. And why it can be used as an easy microcontroller, in space etc
@@acmenipponair Exactly, that's why I loved it, too. Around 1983 I then switched to Z180 when my products needed more memory. It was such a joy to work with, I wrote tens of thousands lines of assembly language code for it; I doubt modern day designers can experience such an intimate closeness to the machine. 🙂
It would be like using a racing car in a shared space zone.
Reminded of writing Z80 hex for a Spectrum into the wee hours. I was 20, working unskilled jobs, knew nothing. BASIC was okay for programming concepts but it gave little idea of what was actually happening and I needed that. Things started to click when I realised video was just part of the memory. First tools I wrote were an assembler and a text editor, it didn’t really occur to me these would already be available. Then discovered C and compilers. I think, without that grounding I’d have not ended up working in IT. Thank you Sir Clive.
Z80 had a great run. Back in late 80s it was the first CPU I programmed directly in machine instruction code (yes, converting instructions into hex numbers, calculating relative offsets).
HiSoft Assembler and HiSoft C were my first development editors or IDE for ZX Spectrum.
@@MrDiverzija Hisoft... Devpac, C and Pascal.
Reminds me of my days as a Technician who inherited a microcontroller design from a departed engineer. It was 68HC11 based with a UV EPROM for code execution. My tools were a text editor (B) and the motorola AS11 assembler with debug done with a logic analyzer. Burn & Crash FTW. I hated waiting on the UV eraser box.
I learned Z80 assembly while unemployed in 2020-2021. I also learned 6502, but I prefer coding on a Z80, 100%
@@TheNuje Try 8086 assembly. It's akin to Z80 but with still more registers
I honestly thought the Z80 might never leave active production. What a great piece of technology history!
So finally after 50+ years the 6502 vs Z80 war is over, winner by default the 6502! 🤪😜
😂
@@thudtheace As a happy owner of both (I had an Apple II and Sanyo MBC at the same time) it’s just a joy to have watched the race.
@@thudtheace Acorn originally adopted the 6502. Then they developed their own chip called ARM, which is very definitely the winner in terms of volume shipped.
@@katrinabryce Here you are wrong. Because ARM is NOT a chip - it's an architecture. There are many many many different chips using different ARM versions, but the original chip only was produced for some years. The 6502 is a literal chip that is produced until this day. So when it comes to the chip war, the 6502 has won. When you would compare architectures, then the x86 is still the winner, as any chip produced by Intel or AMD at the moment is based on the x86 architecture, just much more modern.
I still have my Timex Sinclair 1000 in storage. It was my first computer and introduced me to the field. I've recently retired as a Network Administrator after a long IT career, all because of that Z80.
Lovely story!
I started with the Timex Sinclair 1000 back around 82-83 maybe? Learned the little simple basic they had at the time, and eventually how lacking it _could be at times_ , so we moved right into poking code directly into memory. Loved playing around with that thing... even remember seeing an article for a voice recognition program (since you could use the MIC in/out ports normally reserved for saving and loading programs).... I've been a tinkerer ever since then, with only a short break due to my first marriage. Should have just stayed in playing on the Sinclair in retrospect!
At any rate, kind of the same story. Once I got back into things, Windows had came along and progressed fairly well. I've been playing catch ever since. However, I'm now at the point where I have completely left having to go out to work, and do everything from a little home office now as well.
That little Sinclair was some great times and good memories, and undoubtedly led to many many individuals making everything run today! I just didn't realize how many things the Z80 was actually in...!!
Same here but ZX81 😂
Started coding at age six on the ZX81. Continued with Commodore, Atari and then Apple for the last 30 years. Missed the Windows-boom… 😂
@@UserDefaultEurope I still use QuickBasic..... it's from 1988...
Many years ago I had a Heathkit H89 computer which used two Z80 cpus. One of the Z80s was on the main computer board, the other Z80 was on the video terminal board. This computer could run two operating systems. One of the operating systems was Heath Disk Operating System, known as HDOS. The other operating system was CP/M.
It could also run UCSD pascal, which was its own operating system with a p-code interpreter integrated into the p-System (the name given to the operating system). Capable of concurrent multitasking at a time when MS-DOS was strictly single thread. The performance of the H89 was, for the day, remarkably good. We used one in conjunction with an external box, to emulate a wide range of CPU's in hardware and driver development. Ultimately UCSD priced itself out of the market.
That sounds awesome. I've never heard of that system. You've given me something to research. Thank you 😉
There was another version of this computer. The kit form was called the Heathkit H89, the fully assembled version was marketed under the Zenith Data Systems name as the Zenith Data Systems H90. It is too bad the Heathkit and Zenith Data Systems went out of business.
@@davidgrisez I'll check that out as well. Thanks
@@davidgapp1457 It''s a shame because the p-system is inherently portable and could easily adapt to new cpus. SofTech dropped the product, and it was picked up by Pecan Systems, owned and run by real enthusiast users. But the market at the time wanted to coalesce around a single OS, just about any microcomputer OS might have been embraced, but IBM PC-DOS and MS-DOSes turned out to be that, although early MS-DOSes, were really a bunch of incompatible OSes. Compaq, Phoenix and the other clone makers fixed that.
I am surpried that no credit is given to Ted Hoff (Intel employee No.12). Hoff came up with the idea of using a "universal self-contained processor" rather than a collection of discreet chips. He designed the instruction set for the Intel 4004 with Stanley Mazor in 1969. Development of the actual 4004 chip was done by Federico Faggin, as mentioned.
They are all credited with the invention of the Microprocessor.
I'm from Germany and bought a TRS80 Level-II compatible computer in 1982 or so, which I still have and it's still running. I expanded the memory from 16kByte to 32kByte using a piggyback memory chip.
Back then, for lack of opportunity, I learned the Z80 mnemonic (load register, shifting, ...) and programmed the TRS80 directly. What a fun time. Used my cassette deck as a storage device - I didn't have enough money for a floppy disk drive.
Didn't know the Z80 has been in production since 2024.
Thanks for your video.
Glad you enjoyed the video, lovey to hear of your trs-80 story!
good times... Z-80 was first CPU, I programmed in assembly.
Same.
same.
same.
Mine was the ubiquitous IBM 1401, the assembly language being autocoder.
Assembly? Pah! It was machine code all the way when I was a lad.
Thank you for this respectful homage to a great idea; regardless of the z80 being their peak or not - It is most definitely valid to say that we owe Zilog a lot!
Thanks for the kind comment!
@@AlsGeekLab You're very welcome, thank you for your effort to entertain and inform - You da man!
I found this video fascinating and sad in some ways seeing at the same time seeing an old acquaintance retire but then again technology moves on.
From 1980 to 1987, I worked for Visual Technology. Visual used the Z80 almost exclusively in their terminal products except for one model that came out in early 1987 which used the 68K. In addition to their terminals, they also produced a couple of personal computers, with one being the V1050. The V1050 had both a Z80 for its main operations and a 6502 for graphics allowing the system to perform some amazing tasks and ran CP/M Plus.
As a technician, I knew the pinouts inside and out and while attending night classes towards my degree, I took a class in Z80 Assembly language which was offered at the time. As it turned out, the professor owned a Visual V1050 and I ended up repairing it for him when it crashed. For our class project, we used Apple II computers with that Z80 card installed. All it took was a simple key-combination that switched between Apple OS and CP/M 2.0.
I had a TRS-80 and often used EDASM (an editor and assembler).
You could do nice things with the memory-mapped display.
One thing I remember was a 3D game-of-life program I wrote in assembly.
At the time you could really fully understand a PC.
I soldered another 3 sets of memory on top of the 16 KB RAM and added an address decoder to create a whopping 48 kByte RAM.
Also a lower-case character generator as the base TRS-80 only had CAPITALS...
I did quite a lot of 'upgrades' for the TRS-80 screen memory, but it only took a single 1k x 1bit SRAM chip (from memory a 2102 or something like that) piggybacked on one of the already installed SRAMs with the chip select line taken off to pick up from the main RAM. I used to additionally put a toggle switch between two of the ports on the back plain that could turn the chip enable on and off due to many of the PROM masks being wrongly written.
I did all my early programming by hand assembly and then typing in the hex-code using T-BUG. 😁
What an awesome video essay!
I'm 50 years old, & am fully conscious of the wonder, magic & marvel of where we are today.
When I'm at my computer - I'm aware of the entire history that got us to this point - & that I get to interact with this technology, just like that.
At school - we had the Tandy green-font computers, & later on in Secondary school (c. 1982+) - the BBC Micro. Plus some Apples - which were in the 'graphics' department.
Thanks for your kind words 🙏
This is a brilliant documentary. Just to add, $26 in 1976 was roughly half a week wages in a ordinary job today. By ordinary, I mean somewhere between a retail worker or delivery driver. I still believe in the Z80
That's like 100 bucks in today's dollars. Retail pays around 15 bucks an hour. So its more like a days pay.
Thanks very much for your kind words! It was still a decent chunk of change, but certainly affordable compared to the thousands of bucks Intel would charge. Only after the success of the 6502 and Z80 did Intel & Motorola see that computers could be in every home and office and started to scale their prices accordingly
When the 8080 was first released in 1974, it cost $360, so $26 was a very good deal for a processor with better performance!
@@mrodby yeah, the Z80 was chump change compared with Intel!
@@arthurswanson3285 Definitely part time if you were earning only $2.85 - $3.35 per hour.
I was genuinely sad when I learned that the Z80 was end-of-life. End of an era.
Cheer up, this is not an end of an era yet. Z80 is dead but eZ80 still lives on. Same instructions, better chip. And some small Chinese company might still pick it up anyway.
Wouldn't be too concerned. There are millions of Z80 based chips out there - including SoC versions of the Z80. In addition, you can emulate the Z80 in a FPGA (or similar) which yields a performance considerably superior to the stock chip. Personally, I bought one of the Spectrum Next Edition 2 which took me straight back to my first computer!
Lived with it for few years as a designer and liked it
I was actually amazed that it was still around until last year!
@@davidgapp1457 I'd think some foundry in China would just re-silicon-compile the Z80 into a modern process and continue manufacturing.. Likely get a must faster version of the part as well.
I had a rare chance to meet Federico Faggin in person last week. What an amazing guy!
Amazing! What did you say to him?
@@AlsGeekLab He said, "Faggin, sounds like vagina"
@@AlsGeekLab Why didn't you make the R register 8 bit?
He didn't say much he was busy faggin
@@AlsGeekLab he had a new book out and the topics were not about 8 bits - more about life and what might be behind
0:27 the shown TI89 is based on the 68K from Motorola. I believe only the TI84 series is powered by a Z80 derived MCU.
well, for that matter the GameBoy and probably others, are "Z80-derived" and not actually Zilog's chip. TI83 series also had Z80, and if you want to get really pedantic, the "TI84 series" is always referred to as the "TI84-Plus" series, in Texas Instruments documentation.The 83 got an upgrade to "Plus" and they kept "Plus" in the names of all the TI84s.
0:27 The pictured TI-89 actually used a 68000 but some TI graphing calculators do indeed use a Z80 (or an eZ80 these days).
Thanks for the heads up. I knew some of them did, didn't specifically know which ones
Yes , but all Texas graphic calculators before Ti89 used Zilog cpu
@@edwardteller5879 TI-81 to T!-86 used Z80, and so did TI-73. The earlier TI-80 used some weird Toshiba thing. TI-89, TI-92 and TI Voyage 200 used 68000.
@@ijabbott63 you forgot the T83 series and TI84-Plus series, unless I am misinformed. The first TI-80 Pocket Computer used two 4004s. Not in any sort of "dual core" set up or the equivalent, Sharp (these were re-branded by TI) just divided CPU functions between the two. This is the kind of fact that AI hallucinates on, I'm sure confusing The Pocket Computer with the other TI-80 microcomputer line. The Pocket Computer heavily marketed on it's ability to do BASIC, which at the time made it not a calculator, at least according to TI marketing and their literature, anyways.
@@squirlmy I was including the TI-83 and TI-84 series within "TI-81 to TI-86", also including the TI-82 series and TI-85. I was mistaken about TI's first graphing calculator was the TI-81, not the TI-80. The TI-80 graphing calculator came several years after the TI-81 and was unusual in not using a Z80.
I think you were thinking of the TRS-80 pocket computer.
I still have a Z80-powered clock, built from a kit. It picked up the 60KHz radio signal from Rubgy, UK. The signal contained the date and time from an atomic clock, and was sent as a fast data burst in the first second of every minute for equipment capable of reading it, followed by the same information transmitted as pulses at 1 second intervals for slower eqipment. It has no RAM, just an EEPROM with the code and a bunch of chips to drive a 6-digit 7-segment display. It's called the REWBICHRON, published in Radio & Electronics World back in the 80's.
Ah.....Ambit International
Our company used the Z-80 as our workhorse in the early 80's. We used it for many of our embedded systems in prototype inspection equipment. A group of us created a transportable robot to solve the Rubik's Cube in 1982 and even published some papers on it. Such great memories!
I really loved the assembly language mnemonics of the Z80, as it was so much better than those of the 8080. My first real computer after my Apple II was a Columbia Data Products 964 Commander running CP/M, with dual Z80s and dual banks of 64k ram. It was essentially two computers connected with an internal serial interface, where one system was responsible for screen output, and the other for running applications. I even had an arithmetic co-processor to handle trigonometric functions. There were no built-in functions to draw a line or shade a polygon, so I had to write my own in assembly language. I paid $4000 for it around 1979 (a huge sum of money) and developed a 3D solid modeling application in FORTRAN which I sold for $17,500 a year later.
Well that was a solid profit I guess! Fascinating sounding machine and bit of work!
The instruction set still lives on in the eZ80 soc.
I loved the Z80 and used it for real time industrial controllers. It had two separate sets of hardware context (registers and the like) So I kept the real time stuff in one context and the non time critical stuff in the other context. This allowed me to take a timed synced interrupt, and do my real time work without have to push and pop registers to the stack. I used the other context for supervisory work like a console, reading buttons, printing reports and maintaining production logs. Now I am amazed with what I could to with 16 kb of rom and maybe 4 of ram.
Very cool! 😎
@@AlsGeekLabthe Z80 CPU was a good system to use, but it was only 48 Years of age when it had suddenly failed in 2024, after it was completed in 1976.
This video just reminded me that I have a Z80 kit which needs debugging. In the early 80s I worked in distribution and we sold the Mostek MK3880 and the NSC800 the first CMOS Z80/8085 clone (but not pin compatible). I worked as a programmer with the huge (the aircraft carrier) Hitachi HD64180. To this day I can take a hex dump and disassemble it in my head.
TRS-80 Model I / III were the first two computers I programmed on in the early 80s at school. Our family's first computer was a Kaypro II in early 1984. All of these beauties powered by the Zilog Z80.
I put together a TRS-80 with the Z-80 and I used that thick book which had the instruction set in it( I threw it away and I wish I hadn't) to do all sorts of things in assembly. This was in 1979 I guess. Because I had done Fourier Theory a few years earlier I actually did an FFT in assembly and finally got it to work. The file was on a cassette. I never did programming as a career as I was more an applied mathematician. Years later when I was doing the Giant Mersenne Prime Number Search I came across a programmer who had programmed an FFT for the large number multiplication used in that application. It brought back memories of the Z-80.
Are you referring to the ubiquitous "8080 Bug Book"? Its available on the Internet Archive.
@@dennisfahey2379 No it was a Zilog 80 book. It could be on the archive though. I will have a look. Thanks.
Was a 6502 kid myself. had some neat tricks of it's own with zero page address redirection saving many cycles to perform similar... also able to rewrite it's own code because of the shared memory space.
Don't get me wrong the Z80 was a beast... but I had to make do with what I had ;) The real issue was that neither Zilog or Rockwell were quick on the uptake of SOC so most of the first generation of embedded's ended up being 8088/6 devices. Dallas Semi took those and ran making some really cool ultra low powered devices with some exceptional low power static ram stuff based off of the 8051 architecture.
I am happy to say that I love the 6502 and Z80 equally 😍
6502 at home, 8080 in school. Both had easy to learn layout and instruction set. I preferred 6502 because of addressing modes, but had nothing against 8080.
I've become a fast fan of the Geek Lab and I'm stoked at your success!! Dude - yer a TH-camr!!
You rock! Thanks dude!
I learned about microprocessors via the Z80 and building my own Z80 based microcomputer as a lab project in college. That knowledge has stood me in good stead bringing many Z80 things back to life, both in industry as well as electronic music instruments* for hobbyists.
(*): extensively used in those as well, with some frightening shortcuts taken in terms of digital design, to where I sometimes wondered how they ever worked at all. But: replace the faulty component (in 30+ years I've only seen 1 actually faulty Z80 CPU) and these things just spring to life again. A remarkably robust and forgiving design.
I made a fully functioning emulator/debugger of Z80 on a PC in Borland Pascal back in 1994. Will never forget that good old processor.
I still have fine memories about Borland Turbo Pascal, the integrated compiler debugger compiler for pascal. Great for quickly writing engineering software.
@@reneverstraeten Turbo Visions forever!
Thanks so much for creating and sharing this informative video. Great job. Keep it up.
Made a project when i was in the sixth form (1980-81) - disco light sequencer built around a Z80A. Hand compiled assembler into a 2716 UV EPROM. Hand drawn photo etched PCB. It eventually died when the NiCd battery leaked and ate the track!
My first computer in 1982 was a used TRS-80 Model III, with a cassette as it had no floppy or hard drives. The programming foundation I got then from still serves me today.
A small addition to your fine video. The Intel 4004 was widely used as a traffic light controller. I too owned a TRS-80 in 1980. The most interesting Z80B fact that I can add is I remember seeing a Z80B chip used on a Parallel Interface Card built for the ISA bus on a PC. The CPU that ran the whole computer was now relegated to running the printer interface. One hell of a printer card if you ask me!
Back in 1978, when I was eighteen, I bought one Z80, along with eight 1Kb DRAM chips (which were more expensive than the processor itself), and I tried to create my own personal computer, using NASA"s apollo 11 wrapping technique for the wiring. That was five years before Apple II... I even hand-coded a BASIC interpreter in Z80 assembly langage. The Zilog Z80 was so much more cool and powerful than its closest competitor, the Motorola 6502! Its instruction set was so clever! Later, I had a TRS-80, then a Sinclair QL (wich has a 68008 processor, another landmark in the area of microprocessors), and an Atari 1024ST... But I will never forget the Z80. RIP!
Back in my 6502 days I rewrote lots of code from Z80 to 6502 or more rarely, a high level programming language. I perceived the 6502 as minimalistic, the Z80 as pretty quirky, borderline ugly. My next major architecture was the 68000, 68010, 68020, 68881/68882, 68851, 68030. Simpler to the programmer but bloated. The move instruction timing was so complicated for the 68020 that the timing tables covered a double page in the manual. For the 68851 tables became so hopeless that the appendix of the manual contained huge bash scripts to compute execution times. Makes your head spin.
SPARC was weird with its register windows - I didn't like them even when I first read about the in spring of '88. At the same time I read about MIPS for the first time and perceived it as painfully simplistic. It wasn't always obvious how to do some stuff. Some of the stuff took a while to wrap my head around but I eventually became a MIPS guru. Then my IA-64 intermezzo - the philosophy of it never made sense to me. Finally RISC-V which with my MIPS background is a bit like MIPS stirred up, thrown into the air and what falls down is RISC-V. Just kidding. More realistically I'd describe it as RRISC or Reduced RISC. Thinks that even the RISC designers in the 80s didn't dare to remove the RISC-V designers did. Along the way some Alpha. Nice design but sadly primary going fast due to the insane clockrate - one of the technical aspects (think heat) limiting its market success.
The 6502 was from Mostek, not from Motorola. The first 6501 was pin compatible with the 6800 from Motorola and they forced MOS Technology to drop it.
@@0815mklThe 6502 was made by MOS technology, a different company than Mostek.
What a great video, thanks! And shared!
Very Best historical video ! Realy thank you for for this lesson. I was very motivated to learn all this things !
Congrats on this video's success! Any video that gets more views than subscribers is a win 🙂
A great CPU...
... and there are so many of them that we can not run out in the next 50 years! :-)
The 8008 was my first venture into micros from a mainframe background. It really took off with a Nascom Z80 kit for which I designed several addon cards as well as embedded systems. The 286 was a step change though, and I still remember prototyping my own designed production motherboard using the Chips and Technology chipset using wirewrap 😁 before going to PCB. Huge progress since in both SoCs for embedded systems all the way up to my current OC'd 14900KS monster. Memories ❤.
This is like finding gold. Such a blast from the past for me. Subbed here!
Except the Z80 only has a 4-bit ALU and lots of its instructions are on one end of the clock tick. The 6502 has a true 8-bit ALU and it can process instructions on the top and bottom of the clock tick. If both at 1MHz, the 6502 far outperforms the Z80. That's the key isn't it, the Z80 was usually at 3.25MHz, 4MHz or some faster speed, so the Z80 seems better at first.
Yes I think that's why I said that the 6502 was better on paper. The Z80 outperformed it because it was provided at greater clock speeds than the 6502 at the time
Who cares perf/Hz? Who cares ALU width? Only perf/dollar matters!!
and again the same stupid mhx comparison which does not mean nothing. a 6502 @4Mhz require so much DRAM speed that with the same memory chips you can interface a 16Mhz Z80! so the ratio is the same. the apparent efficiency on 6502 is due to the double clock usage while the z80 use a faster single clock and divide by 2 or more the clock to perform its internal operation while the 6502 used the clock "as is". What does matter is the amount of operations a processor can do at maximum clock rate, not the maximum clock rate itself. On this side a z80 CPU outperform the 6502 by 20% to more than 200%! look for example a full range LDIR instruction which does memory move operations. The 6502 didn't have this instruction and emulating this via code is itselft 3-4 time slower even at same clock rate. OF course this is a extreme comparison and choosing some use cases one can show that the 6502 could be faster than z80 (for example emulating a pre or post indexed memory operations), but in real world scenario one can expect the z80 to be at least 20% faster if both processors were clocked at maximum clock rate. And i was comparing the original versions of both cpus not some enhancements.
The main limit on 6502 is the absence of gen purpose registers ( well, we have register A, X, Y ) which forced a more intensive memory based operations where the z80 could operate internally on registers.
@@AlsGeekLabthey both pretty much maxed out the memory chips of the time.
I guess that is why a few years later CPUs started having internal cache @@peterfireflylund
It's amazing how one little chip could bring so much joy to the world for so long.
I’ve posted this comment on other videos, but… oh well!
My first computer was an Exidy Sorcerer. It had a Z 80 processor, but I’m not sure about the speed. A broken center lead on a big transistor in the power supply caused it to die an untimely death. I still miss it. It was a fun machine, and I learned to program first in BASIC, then assembly language on it. Later on, I was able to use that knowledge to program in assembly language on the IBM 370 and beyond.
My first Z80 based computer was a North Star Horizon, ordered in 1979 and put into commercial use in 1980. 32Mb of RAM and dual floppy disk drives, double sided. Ran North Star OS. Later upgraded to 64Mb to run CP/M.
You surely mean kB, not MB - the Z80 has a 16bit address bus. All it can use without bank switching are a maximimum of 64 kB of RAM+ROM storage.
Also 32MB of RAM in 1979 would have been prohibitively expensive.
@@2K2QkIvP7Cl24k-pq9ou Thank you for the correction. Slip of the pen, as it is so long since I worked in KB.
Thanks for the trip back to my childhood.
I learned to use the computer on a machine with Z80A and 64 Kb RAM...it ran CP/M 3.1 on it and brought with it an overwhelming amount of software. In the years between 1983 and 1985 I learned to use C, Macroassembler Z80, DBase, COBOL, Basic (two or three dialects), all stored on big 8-inch floppy disks (and 1.2 Mb capacity). It seems like yesterday, but forty years have passed. Still, the wonder that chip had aroused in me I will never forget: heartfelt thanks to my fellow countryman Federico Faggin for all that...
Time for me to stockpile them. A few of my carwash logic systems run on z80s
Love Z80 ❤❤❤❤❤❤❤❤❤
So there were still fabs around making chips on 4 micron? Im surprised the die hadnt been shrunk more over the years.
in the U.K. I built a nascom 1 and 2 from kits in the late 1970s soldering the components to the pcbs and learnt to program on them, Z80 assembly code and tiny basic , I owe so much of early career to the Z80 thank you for the video. Future generations should be thankful to such brilliant minds that have given us the modern technology all take for granted.
The Z80 is my favorite CPU alongg with the 6502. I've always wondered how fast they could be if more modern processes were used to make them, say 90nm or something. Of course the die would be so small that a very accurate tiny robot would have to package it, but they could get millions from a wafer.
They could indeed be wicked fast, but without intermediate internal cache augmentation or simply incorporating all system memory on-chip (yesterday’s system memory size is today’s cache size), it would spend vastly more time in wait state’s than execution.
Being born the same year of the Z80 and growing up with 8 bits computers and arcade games I’m feeling old…
Me, same year, same feeling 😂
I was born the same year as Unix, about the same time as the equivalent of Unix 1.0. To really geek out, my birthday in Unix Time is in the low millions, but saying this doesn't make me very popular at parties for some reason
i still got my speccy from 82 and i feel... not old. irresponsible maybe.
Thanks for this super interesting video on an old classic!
I remember this well, as I worked as a bench tech repairing 8/16 bit cpu board. Thanks for sharing.
The Z80 will live on into perpetuity through its FPGA core. Love it, use it often. Yeah!
My first system, and first assembly I learned. A rare 'Exidy Sorcerer' with rom cartridges and Kansas-City tape interface. Ahh... those were the heady days of user groups meeting in person to exchange cassette tapes of programs we'd spent hours typing in. :)
Same here. I was an active member of SUGT. Sorcerer’s User Group of Toronto! It was my first computer as well. I wrote the Trek77 game for it.
My first computer was a Cromemco Z80 system on an S100 bus, with 64K RAM and two 241K 8" floppy disks running CDOS, a CP/M clone. Later I upgraded to a (massive!) 10MB hard disk, and recoded the OS to support it - not too hard in those days, with just serial port and two disk drivers needed. That computer did a lot of work for me. Simpler times indeed!
That would have been a really cool experience! If you'd ever feel like having a chat about your machine on the channel, I think that would make a great story! Drop me a line if you would like that!
Please let us know more about this. We need to be able to record the stories you have in order to learn.
Lots of memories to dust off - I'll see what I can do.
I built a Cromemco Z1 kit for my college in 1978. Like your machine, ours had 64K RAM and two floppy drives. We used the machine in our computer science classes to study operating system design as our IBM Remote Job Entry system into an IBM 370 limited our ability to get down to the hardware level and write device drivers. Upon graduation in 1980, I joined Mostek and became a factory application engineer on the STD bus which was based on the Z80 chip family
@@mbilden I've summarised it, but its too long for a posting here (just over 2 pages). Any suggestions?
In 1972 Rockwell released a 4 bit CPU that consisted of a three chip set. My first job as an electronics engineer was with a company that produced a product call a 'computing integrator' which was used in conjunction with chemical analyst instruments. The first gen used discrete ICs. 2nd gen used the Rockwell set. Third gen was Intel 8008, followed by the 8080, and then the Zilog Z80.
Still (as a Brit) struggling to come to terms with someone with a Scottish accent refering to this chip as a ZEE Eighty. I've always called it the ZED Eighty. I first started to use and program this device in 1979 using a Zilog MCZ-20 development machine using the RIO operating system. That's it at 1:09 (the blue box with the cream lid) and I wish I'd kept this machine instead of putting it in a skip all those years ago.
I literally had to write zee 80 in my script to say it that way. It was an American product so it's called a zee 80 by Zilog so it is only right to call it Zee-80. In my head I was screaming every time I said it though!
The Z-80 family was the first processor I learned to create systems with: both hardware and low-level firmware coding. I keep a warm memory of those times 🙂
I am fortunate to have worked with the entire Z80 family to the point of memorizing their pinouts and the CPU instructions, being able to write assembly code and immediately translate to the opcodes. Fun times indeed but sad as it is the end of Z80 production, progress always moves forward.
Lovely overview! Thanks it was very enjoyable!
Glad you enjoyed it!!
NASCOM 1 was a British SBC that used the Z89, 1k RAM, NASBUG the machine code monitor on PROM, real keyboard and TV modulator output.
Got the original zilog technical documentation for the z80. Need to review it and remember.
My first interview to be a professional programmer after finishing college here in Ireland was to be a Z80 programmer for embedded telecoms units for Motorola.
That was 1998.
I was shocked/surprised that the processor that I knew from old home computers was being used to run mobile networks! In hindsight, I ought not have been. Was a great implementation.
I didn't take the job. Went and used this new language my buddy told me to learn for my final year project - Java. Ended up going enterprise, baby! 😕
Feel lucky to have found this a few days after the Zilog announcement. Are there any other late-70's "mass market" chips still in production now?
Winners and losers in the high-stakes game of early tech adopters... It's an enthralling set of stories. "Gary Kildall's CP/M" - I'm glad you called it that each time.
Thanks for this, I love this class of content. Subbed 👍
Great video. Thank you 🙏
Glad you enjoyed it 😁
My father bought a TRS-80 Model I, when they first came out. We had it at home for quite a while and he and I taught ourselves to work it and do some 'BASIC' programming. They didn't really have computer courses at colleges and universities back then, you had to teach yourself. Later on we (Dad's office) had the TRS-80 Model II, and then went to the TRS-80 Model 2000. This was all BMS (Before MicroSoft) ... Jobs and Wozniak were busy tinkering around in their garage creating Apple computers.
I did a course at college one time as a 'mature' student, and most of the students were fresh out of high school. I don't think any of them believed that there were computers around before the IBM PC and Microsoft WIndows ... etc.
Z80 was the first CPU that I worked on..as a college group project...
was able to have that project successfully running on breadboard... to the delight of my professors that time...
our group passed that course...
Only issue is the TI-89 you displayed as a Texas Instruments Graphing calculator doesn't contain a z80, rather a 68k.
I ran a Dahlgren System 1 engraving machine off a TRS-80 back in the day. It was literally a desktop CNC machine!
Back in 1994, I have built a very simple development system based on a Z80, as part of my robotics diploma project at BCIT. A single-sided PCB for processor and memory, point to point wiring on a perfboard for IO. Four-digit LED hex display with a 16-key keypad for program input. Program storage on an UV erasable EPROM. The idea was to servo control a motor. It was certainly more fun and educational than buying an off the shelf "student" system. It's surprising to hear that this ancient architecture is still in use.
And likely for many years still to come!
The early 80s also saw a Z80 clone, called the U880, that was one of the most widely used chips in the eastern bloc. One of these powered my first home computer (KC85).
No wonder why someone want a 100Mhz 6502.
Best instruction set ever !
That's until you meet Motorola's 6809. (Not so popular because too expensive)
With appropriate cooling current generation 65C02 can run with 100Mhz.
@@Martin.Krischik How hot it could be
@@thanatosor Hot enough that you would need active cooling.
The PDIP-40 can run up to 14 MHz without additional cooling according to the data sheet but nothing stops you to clock it higher.
Well, the capacitance of the PDIP-40 will eventually get in the way. But there are PLCC-44 variants which can go further.
Provided you add sufficient active cooling. You should not do any of that for production environments of corse.
Great video! What resources did you use for your research? I don’t see any sources listed in the description…
Various sources, I don't have the script with me right now and I made the video over two months ago (it's been up on my Patreon channel a while). I believe some of it was Intel archives, computer museum, excerpts from interviews from Faggin and also Wikipedia where I could cross-check.
Do you typically not post them or will they be appearing later? I wrote a piece on the same subject and would be keen to expand on my piece with some of the other things you mentioned here. 😊
Back in the day I made an adapter card with an NSC800 (CMOS with Z80 instruction set) for my IMSAI 8080. To match the 8080 pinout and ROM timing a few inverters and bit of logic to add a wait state were needed. But it doubled the CPU speed and expanded the instruction set. Those were the days.
Awesome engineering dude!
@@AlsGeekLab The original NSC800 was a drop in replacement. Then the lawyers got involved. They had to make it incompatible. I just unincompatibleized it... well, and added a wait state in the ROM address space.
The last thing I designed was a 10kV 5A power supply for the power oscillator (a water cooled tube) of a cyclotron. Why a tube? It lives in a high radiation area where solid state stuff goes to die.
I didn't know the Z80 was still in use until recently. I have an Osborne 1 in my attic, learned a lot from it. It got me started on a 40+ year career in IT. Now I'm mostly retired.
It’s in the Mega Drive/Genesis as well. Along side the Motorola chip. It handles the sound and since it’s the heart of the Master System also handles the backwards compatibility. It’s truly a legendary chip.
I still have a Sharp MZ 80-K in my loft somewhere. Loved coding in it.
What CPU architecture will be the first implemented in graphene? 6502, z80, risc-v?
Guess, what... I still have a few, brand new in their package. Great video !
The Z80, the Sinclair Spectrum, the Commodore 64, and all the people behind them… Thank you 🫡
These products and people, even the ones writing those zany gaming magazines of the 1980s/90s, defined my life and made the world a much happier place! 🤍
"Gary Kildall: The man that could have been Bill Gates" I can't help but think that the world would be a much better place if that had been the outcome in this timeline...
The shop I worked in (1976-80)sold the Exidy Sorcerer, a Z80 micro, around 1977/8. Not a bad computer, it had 16 or 32k of RAM, could load and save to casette and you could plug in ROM modules (a PCB inside an 8-track cartridge!) for word processing or BASIC programming; other applications were planned but I never saw one. Then it got a disk drive unit that took 100k floppies or even a little hard disk, but that loaded MSDOS instead of the cartridges and took almost all of the working memory, leaving about 1.5k. I did write a stock control system to fit, but I had to use random access files on the floppy, making it slow.
Museum piece now, of course.
A few years ago, I threw out my Jupiter Ace, another Z80 machine, on the lines of the Sinclair ZX80, running Forth. I now find that they change hands for hundreds of pounds. Some you win...
And, Al, why are you saying Z the American way? Makes the video annoying. Very annoying.
the one that started it all for IBM in the personal market.
Great Run
I have to wonder why the production was stopped. Change for the sake of change isn't usually good.....
Very informative upload, great job ! I learned something here today, and I thank you, sir.
I'm surprised that Zilog never went after the potential performance benefits of switching for a full sized 8 bit ALU to the Z80. I guess while it would still be instruction-compatible, the timings would change, which could affect certain applications of the chips that had code reliant on many clock ticks each instruction used.
That’s exactly what follow-on variants did do, but they dropped out of the PC race and receded into the lesser known embedded world.
Interesting point, thanks for the follow up @chrissmith-tc4df too!
0:31 I think the C128 was 6502 based. Like the C64 vic 20 and apple 2.
The Z80 was the second CPU I learned to program on back in the late 70's. The other was the 6502. After going through TRS-DOS and CP/M on my TRS-80 Model 4P, I didn't see the Z80 again until 2012. I got hired at a low-energy lighting company that used PCM to send current down a CAT-5 cable to effectively bit-bang a Z80 into powering LED lighting fixtures. The BOM on the Z80 made me laugh: the Z80 was a show-changer in its day, set my career going, and then heading into my final lap, I got to work with it again on a product that conserved significant energy, and did lots of cool stuff like follow-the-walker lighting. The unit had the Z80, the light, and multiple movement and temperature sensors. Brought joy to my heart to hook up a JTAG and reprogram it with my latest firmware install. Sorry to see the Z80 go. It served me well.
Absolutely SUPERB vId. The Z80 is dead, long live the Z80. Now for memory only ( no pun ) 21 LD HL 3E LD A. .... I have to stop, the wonderful memories of this chip planted in a Trash 80 was jut the ultimate for hardware / software playtime. Thks again for a great history vid, there are a good few things I did not know here even after all these years. Very well done sir.
It was the main CPU in a C128 *if* you booted the machine in CP/M mode.
Normally the machine booted with the 8502 as the main CPU.
I just got ahold of my childhood TI-84. While not from the era where the Z80 was a power house, it makes me want to finally take a dive at assembly and see what I can do with it.
Great video review, i love the Zilog 80
The dear old Z80.
The most important and certainly the most creative and fun part of my entire career as an electronics engineer was designing circuit boards, writing assembly language programs and inventing rather elaborate data acquisition systems, many of them using the STD bus and all based on the Z80. I was the company's microprocessor 'guru' and had my own lab. In my lab, I had a powerful advanced microprocessor development system designed especially for the Z80. Using the development system, I could compose assembly language programs, burn them into UVPROMS and then use the system's powerful emulator to debug the resulting system. With as little as 1K (as in 1000) of 8 bit bites, my little boards could sing and talk back to you and tell you what was going on inside complex systems, machine instructions burned into a PROM were that efficient. One of my boards that put out a whole range of phase variable test signals for testing Atlas rocket servo systems had no external RAM, but relied on juggling variables in the many registers in the Z80. This specialized waveform generator replaced a wonderfully complex (and rather brilliant) electromechanical system that used a rotary core 400 Hz transformer and very elaborate mechanical relay logic (originally designed in the early 1950's) that took up a whole cabinet (the 380 cabinet) whereas my Z80 equivalent was on a single 4X6 inch board. The other engineers wrote their test procedures and other work out by hand on paper tablets and then gave it to one of our secretaries to type up, but not me. I used the development system's editor to type up my own work myself and then I'd print it out on a large professional dot matrix printer. Those were wonderful and heady days and looking back today, I feel privileged to have been able to experience them. All this was thanks to the dear old Z80. By the way, I still have my TRS-80 that I used to teach myself assembly language programming before I got the professional development system.
I used to program on the 8085 for many years doing video games and traffic signal controllers, all in assembly.
Now that takes skill!
programmed both the z80 and 6502 in assembly. Both great chips. But at the same clock speeds, the 6502A much faster at everything not needing 16 bit indexing. Primarily due to it's use of s-ram instead of dram and it's zero page addressing mode. I haven't got the manuals any longer so don't sue me here. But I think for example the z80 DJNZ instruction was 7T states, where as DEC xeroPage and BEQ were only 6T on the 6502. Either way though, both great chips... thanks for the trip down memory lane.
Sega Genesis/Mega Drive had a z80 to act as a sound cc-processor and for backwards compatibility
Indeed it did, I could have spent a loooong time reeling off the many uses it had but I had to stop somewhere!
I was a 6502 guy but I mourn Z80 the same. Still have one in my Microsoft CP/M Card on Apple IIe
i've learned soldering with the z80. the ndr-klein computer was a modular selfbuilt system. one could
build a full system from the scratch. i bought the empty boards and books (that's what i could afford) but had good connections for the chips.
Great video!
Thank you!!!
My first assembly level programming experience was on an HP-125 computer that had a 4 MHz Z80A CPU.