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MightyPEZ
United States
เข้าร่วมเมื่อ 3 มี.ค. 2022
Sinclair ZX81 Keyboard and Power Regulator Replacement
Fixing a ZX81 with a disintegrating 40 year old keyboard membrane and replacing a LM7805 linear power regulator with a switching regulator in a TS1000. Also in the video we measure the reduced power usage and heat reduction after the upgrade.
Items shown in this video:
Recom Power - R-785.0-1.0 (DigiKey)
ZX81 Replacement Membrane Keyboard - Various vendors
Previous Video comparing Linear and Switching power regulators:
th-cam.com/video/JYU72UXcwuQ/w-d-xo.html
Music from #Uppbeat (free for Creators!):
uppbeat.io/t/andrey-rossi/seize-the-day
License code: Z0QCQGPXFVQPMYNB
Items shown in this video:
Recom Power - R-785.0-1.0 (DigiKey)
ZX81 Replacement Membrane Keyboard - Various vendors
Previous Video comparing Linear and Switching power regulators:
th-cam.com/video/JYU72UXcwuQ/w-d-xo.html
Music from #Uppbeat (free for Creators!):
uppbeat.io/t/andrey-rossi/seize-the-day
License code: Z0QCQGPXFVQPMYNB
มุมมอง: 32
วีดีโอ
78xx (LM7805) linear vs switching voltage converters
มุมมอง 10421 วันที่ผ่านมา
Comparison of the standard 78xx (LM7805) linear regulator vs. switching regulators for voltage conversion. I am working on a project where I want to reduce heat, so I am starting with reviewing options to replace the LM7805 voltage regulator with a modern switching regulator. This is my testing as I learn the differences. Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize...
Borland Turbo Pascal 3.0 for CP/M 80 on MinZ SBC
มุมมอง 1.1Kหลายเดือนก่อน
I downloaded an configured TurboPascal 3.0 for z80 CP/M on my MinZ tiny single board z180 based computer running CP/M 2.2. Additionally I implemented a short demonstration program to calculate Pi to 9 digits using the Leibniz algorithm. This was one of my primary development tools in College in the 1985 timeframe. GitHub Repo: github.com/RealMightyPEZ/TurboPascal Previous Video on Min-Z and CPM...
Programming Atmel PLDs using WinCUPL and TL866II programmer
มุมมอง 5792 หลายเดือนก่อน
In this video we will create a 7 Segment HEX LED driver using a programmable logic device (PLD) Music: Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize-the-day License code: EW6KLCT0R28REDPO Items shown in this video: Atmel ATF22v10 PLD WinCUPL - ATMEL Programming UI and compiler www.microchip.com/en-us/products/fpgas-and-plds/spld-cplds/pld-design-resources Code: githu...
getting started with CP/M 2.2 on the MinZ-C tiny computer
มุมมอง 3.5K3 หลายเดือนก่อน
This video shows the steps I learned while getting started with the MinZ CP/M system that I bought on Tindie. The system is designed and built by Circle M systems and is based on the Z180 CPU a fully compatible descendant of the Zilog Z80. In this video I: Provide a brief overview of the hardware Configure terminal emulation for command line access as well as file transfer. Demonstrate utilitie...
Automating Test Equipment: UNI-T UTG900 AWG, PowerShell, VISA & SCPI
มุมมอง 1026 หลายเดือนก่อน
This video shows you how easy it is to leverage PowerShell and SCPI to control Lab equipment like wave generators and oscilloscopes. I will demonstrate and share simple code to control my UNI-T Waveform Generator. Code: github.com/RealMightyPEZ/PowerShell-Automation/blob/main/SCPISimple.ps1 Links seen in this video: NI-VISA www.ni.com/en/support/downloads/drivers/download.ni-visa.html UNI-T 900...
MP80 Mk 1 Z80 Breadboard Project Part 2 of 2 (simple programming)
มุมมอง 419 หลายเดือนก่อน
In part 2 of my breadbaord z80 project video I demonstrate manual programming using a trivial example. Code is written in z80 assembler, converted by hand to opcodes and loaded into the system via toggle switches. Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize-the-day License code: NFW8MISLA3SJQDZB
MP80 Mk 1 Z80 breadboard Project Part 1 of 2
มุมมอง 2229 หลายเดือนก่อน
Part 1 of my 2 part series on my Z80 breadboard project. Overview, Architectural review, and simple demo Part 2 include a more in depth demo including hand assemling z80 code. Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize-the-day License code: EPRLKFMTP7ZOUFU0
CPU Clock Circuits using 555 ( 556 ) Timer IC - Z80 Project
มุมมอง 20710 หลายเดือนก่อน
Video describing and demonstrating a breadboard build of multiple 555 Timer circuits which i will use to support my ongoing Z80 breadboard computer project. Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize-the-day License code: SH39VPWLF4UWMDQJ
Debouncing Noisy Switches With LogiSwitch LS10 series IC
มุมมอง 20311 หลายเดือนก่อน
This video explains mechanical switch noise and demonstrates both the issues resulting from and a solution using a purpose built debouncing IC from LogiSwitch. Music from #Uppbeat (free for Creators!): uppbeat.io/t/andrey-rossi/seize-the-day License code: QPP6SK0U3L5HKCQ1
74245 Bi Directional Octal Bus Transceiver ( 74*245 74hct245 )
มุมมอง 2.9Kปีที่แล้ว
Description of the 74*245 octal bus tranceiver and demonstration of its use in a circuit. Breadboard circuit example Items shown in this video: 74hct245 - Bi Directional Octal Bus Transceiver Music from #Uppbeat (free for Creators!): uppbeat.io/t/mojo/rebel License code: 6R4HRCRHXJWYI8HW
Implementing a Toggle Switch using 74*74 (74hct74) D-Type Flip Flop IC's
มุมมอง 249ปีที่แล้ว
I will be describing the functionality of D and JK Type flip flop IC's and then demonstrating how to use them to to build a toggle switch using momentary type switches. Items shown in this video: 74hct112 - Dual JK Flip Flop 74hct175 - Quad D Flip Flop 74hct74 - Dual D Flip Flop 74hct86 - Quad XOR 74hct14 - Schmitt Inverter LS20 - LogiSwitch 9 segment switch debouncer Attribution: Music: Music ...
Digital Hysteresis and the 7414 Schmitt Trigger ( 74hct14 7414 )
มุมมอง 176ปีที่แล้ว
Discussion and demonstration of the phenomina of hysteresis in digital logic. Demonstration and comparison of the 74 series logic IC's: 74hct04 inverter and the 74hct14 Schmitt trigger inverter IC input signal noise reduction Music from #Uppbeat (free for Creators!): uppbeat.io/t/mojo/rebel License code: XDLVHXVHWBTSJAMP
SeeSii FG-100 DDS Function Generator - Troubleshooting and Overview
มุมมอง 4.3Kปีที่แล้ว
SeeSii FG-100 DDS Function Generator - Troubleshooting and Overview Initial troubleshooting of the device after unboxing. Demonstration of the unit once working. Music from #Uppbeat (free for Creators!): uppbeat.io/t/mojo/rebel License code: ULZ8SURKWEHBU885
Great video! Would love to see more CP/M video programming examples (C, Assembly, Fortran ...). Was the pi approximation taken/inspired from a programming book ? I like to read old programming books, especially ones that use numerical examples.
Leibniz formula is one of the very well known formulas, and can likely be found in many programming books, however the formula is well described here: en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80 For more interesting / modern algorithms, I have converted a spigot algorithm as found in this paper to Turbo Pascal: B Rabinowitz, Stanley; Wagon, Stan (1995). "A Spigot Algorithm for the Digits of Pi". American Mathematical Monthly Code: github.com/RealMightyPEZ/TurboPascal/blob/main/Spigot.pas I am hoping to have a video on several implementations running on various 8-bit systems by Pi Day 2025.
Great video, really good demo of transferring files from/to the device. Personally I've played with Z80-MBC2.
I have a SC131 that I hope to build / demo soon. (The parts are staring at me telling me to get at it)
@@mightypez Looking forward to see a video of building the SC131.
Great video. I've bought som SLG46826G PLDs. They can be programmed with an Arduino over I2C, and the software is available for both Windows, macOS and Linux. And they are operate between 1.8V and 5V, with 2 different voltages. I'm looking forward to try them out.
amazing, that the software doesn't seem to have a Y2000 problem - or is the clock set to 1924?
No Y2K problems, no Cyber security risks, no nation state hacker is getting at my CP/M systems. (or my Atari, Coco or ZX81)
Any interest in making one or a few videos about business applications, especially DBASE II (or other database), Visicalc (or other spreadsheet) and Wordstar (or other word processor)? Thanks again for your excellent videos
@@johnzacharakis1316 ahhhh dBase, learned it in college for my one and only undergrad business class. That and Cullinet IDMS were my introductions to databases. Will have to poke around and go find it. Never used Visicalc, i was a Lotus123 user, and still use lotus keyboard shortcuts in excel.
I love your CP/M videos! PLEASE keep them coming, they are very useful and a great reference
Glad you like them! Nerding out with 80's tech has become my relaxation method.
I was a fan of UCSD Pascal and later Borland Pascal. Later I used Borland C for writing embedded code.
I spent countless happy hours programming in Turbo Pascal and Turbo C, then C++. There was Turbo Assembler, Turbo Debugger (which let you use a separate debugging monitor!) They even had Turbo Pascal for the Mac and they developed a really good set of object-oriented GUI tools for DOS, along with the Object Windows Library ... I stayed with them for years as they evolved with the rapid expansion of computing power. But, Borland compilers used to be affordable for hobbyists: now that they've turned into Embracado (or whatever they're called) they seem to want an arm and a leg for the licences and so I use open source compilers when I need to write code, which isn't very often these days. But, fond memories of Borland. Thanks for taking me back in time.
Hi, i had ( still have ) turbo Pascal 5 ( then 5.5 and 6 ) , i was able to churn out code fast once my brain forgot cobol and basic. I then came across technojocks add ons and wow, all the bells and whistles and animated menus was there in my new work
I memeber. As someone who learned how to program on punched cards and typically a several hour wait between submitting a job and discovering you had a syntax error, the introduction of Turbo Pascal was truly amazing.
Completely irrelevant (and enjoyable). When life was simpler. Well presented.
Awesome! Thanks for the video and great work :-)
Maybe I'm just an idiot, but what's the point of this little computer? As far as I can see the only I/O is that USB serial connection. Why wouldn't I just emulate a CP/M machine?
Not a dumb question, really just depends on motivation. For my coding, i prefer the determinism of dedicated hardware, and the knowledge that i am running on actual z80 architecture. But its amazing how many old architectures such as vax/pdp/data general, IBM 370 architecture can all be run with high fidelity on a simple PC or PI emulation. In fact my goal to learn cpm could have been accomplished on CPM/86. Why do i run an actual zx81, 2600, atari 400. Because i am a nerd.
There are advantages in being able to run a program on real hardware. No matter how good the emulation is, it will never match the delays of real hardware. It is quite instructive to build and run same piece of C code on a Z80 CPU with CP/M and compare the timing with the same piece of code running in a simulator where it tends to run much much faster. In the end it is a question of preference for sure. But if you want to have a taste of how it was to use a similar machine in the lates 70's it is quite instructive.
Thanks, this is what I need.
Would it be possible to make a modification and add an interior lithium battery to make it portable? Thank you.
So this means Bus transceiver is protective element for circuit, does't it ? How often can it be happened to have undefined condition in data transmission paths ?
Undefined conditions are due to design errors, not lack of data. Circuit design should 1) prevent multiple active signal sources on a line, (detailed in this video) 2) ensure that no inputs can have a floating signal (i.e. not driven to a high / low state, a rather common mistake that I make and causes troubleshooting)
I got one of these too. It had most of the mechanical issues yours had and suffered from counterfeit op-amps. I was eventually able to resolve all the issues. They can be made to meet specifications. Here are two videos where I go through the steps. 1) th-cam.com/video/sttpgZkDx48/w-d-xo.html 2) th-cam.com/video/XWJOChu1ZMc/w-d-xo.html
👍
Where to buy? Didn't see them at Mouser?
I will have to check Mouser, I buy through DigiKey LS10 series is what I use;: LS18 / LS19/ LS20 LS100 series has additional circuitry for handshake protocol for working with microcontrollers Digikey Ordering: www.digikey.com/en/products/filter/specialized-ics/686?s=N4IgTCBcDaIDYHsDmBLAzgdxQFwMYAsQBdAXyA Guide: logiswitch.com/wp-content/uploads/LS100-Series-IC-Users-Guide.pdf
Thanks for the video. Yes, additional options are always a good thing.
V good
I appreciate what you are trying to offer to the community. But, if I might offer a couple bits of feedback. The images of the charts (as well as the overly long pc breadboard wiring) are almost unreadable. I'm using an Android phone and the charts and images are blurry. I imagine on a monitor, they must be unreadable, as well. Compare them with fellow educators EEV, Mr Carlson's Lab, or Great Scott, as examples. It's best just to show a few wires being inserted into the breadboard, while most of the remainder of the board is pre-wired before the video. I'm going to subscribe to your channel as I like your idea of explaining individual ICs.
Thanks for this useful video. I have few questions: 1) What is the maximum current it can provide? 2) Does it come with a power adapter? If no, which one to use? 3) Can I run it from my computer too? I mean is it possible to interface it with a free software and operate it accordingly? 4) Can we generate frequency in decimals too, like 114.223Hz?
Hello and thank you for your reply 1) Next time I am using the device, I will measure 2) No adapter, it uses a standard provided usb cable, I power it from my nearby laptop, but have also used a phone charger. 3) there is no interface other than the front panel buttons.
@@mightypez Thanks for your reply
Great 👍
I can't hear it ??😢
Sorry to “hear” that. I can assure you I am speaking in the video, and I replayed it just now to verify. Maybe window focus if viewing on phone app?
It not the video... is the generator I got lol
It is inexpensive but wow, way off on max freq spec. What does the filter actually do, clean up the waveforms at all?
I noticed a "slight" reduction in noise (or sometime just shifting the noise) at the higher freq like 10K. it did nothing that would change / correct the underlying waveform, so when they started to break down (square wave looking like Triangle) no benefit. Honestly, after trying it a few times, I never use it. Yes, for me way off, but thankfully I just wanted a cheap low freq sin wave to drive a breadboard circuit clock for low freq testing, so it works for me.