I did everything wrong when fully testing this C128D
ฝัง
- เผยแพร่เมื่อ 30 พ.ค. 2024
- I have this dingy and neglected C128D that I've never even tested or turned on, so let's test this machine and put it through its paces and see if it works or needs some repairs.
0:00 Intro
0:55 Overview of the machine
6:26 Power supply testing
9:49 First power on and diagnostics
39:24 Making a C128 flat keyboard adapter
44:14 80 column mode, SID music and CPM
-- Links
1541 Diagnostic:
blog.worldofjani.com/?p=2180
PSU schematic:
www.zimmers.net/anonftp/pub/cb...
Original C128D:
c128.com/real-commodore-c128d-...
FAST CPM for the C128:
csoren.github.io/c128cpm/rele...
Versa 64:
github.com/bwack/Versa64Cart
Diagnostic harness:
github.com/svenpetersen1965/C...
Lunatico Demo and SIDs:
csdb.dk/release/?id=151273
Kung Fu Flash:
github.com/KimJorgensen/KungF...
Forum posts about C128D/Flat keyboard:
c-128.freeforums.net/thread/1...
RGB2HDMI: (use this fork, it's more up to date)
github.com/IanSB/RGBtoHDMI
Adrian's Digital Basement Merch store:
my-store-c82bd2-2.creator-spr...
Adrian's Digital Basement ][ (Second Channel)
/ @adriansdigitalbasement2
Support the channel on Patreon:
/ adriansdigitalbasement
-- Tools
Deoxit D5:
amzn.to/2VvOKy1
store.caig.com/s.nl/it.A/id.16...
O-Ring Pick Set: (I use these to lift chips off boards)
amzn.to/3a9x54J
Elenco Electronics LP-560 Logic Probe:
amzn.to/2VrT5lW
Hakko FR301 Desoldering Iron:
amzn.to/2ye6xC0
Rigol DS1054Z Four Channel Oscilloscope:
www.rigolna.com/products/digi...
Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier:
amzn.to/3adRbuy
TL866II Plus Chip Tester and EPROM programmer: (The MiniPro)
amzn.to/2wG4tlP
www.aliexpress.com/item/33000...
TS100 Soldering Iron:
amzn.to/2K36dJ5
www.ebay.com/itm/TS100-65W-MI...
EEVBlog 121GW Multimeter:
www.eevblog.com/product/121gw/
DSLogic Basic Logic Analyzer:
amzn.to/2RDSDQw
www.ebay.com/itm/USB-Logic-DS...
Magnetic Screw Holder:
amzn.to/3b8LOhG
www.harborfreight.com/4-inch-...
Universal ZIP sockets: (clones, used on my ZIF-64 test machine)
www.ebay.com/itm/14-16-18-20-...
RetroTink 2X Upconverter: (to hook up something like a C64 to HDMI)
www.retrotink.com/
Plato (Clone) Side Cutters: (order five)
www.ebay.com/itm/1-2-5-10PCS-...
Heat Sinks:
www.aliexpress.com/item/32537...
Little squeezy bottles: (available elsewhere too)
amzn.to/3b8LOOI
--- Links
My GitHub repository:
github.com/misterblack1?tab=r...
Commodore Computer Club / Vancouver, WA - Portland, OR - PDX Commodore Users Group
www.commodorecomputerclub.com/
--- Instructional videos
My video on damage-free chip removal:
• How to remove chips wi...
--- Music
Intro music and other tracks by:
Nathan Divino
@itsnathandivino - วิทยาศาสตร์และเทคโนโลยี
@38:15 "So I could have actually avoided so many of these pitfalls". I couldn't help but laugh after seeing you get several versions of 'PITFALL' on your ROM tester. Accidental comedy at its finest.
I like it when you include all the struggles. It feels super relatable unlike some videos that jump cut out all of the flops. Reading the manual after the struggle reminds me ot that line from Dr. Strange; "The warnings come after the spells!" Thanks for another fun one!
I also love it, this is the realistic process of debugging old stuff, on camera. At least when you have all the tools and spares Adrian has, but waiting for shipping arcane stuff from around the world would not make for exciting videos :D
I'm quite envious of his setup !
But he does cut out a lot of stuff I would like to see
Amen
Some of us love/loved the C128. I upgraded from a C64 in 1985 and immediately took to BASIC 7.0 coding. CP/M mode got me through college computer science, as the software we used in my early classes was also available for CP/M. GEOS 128 was perfect for writing my college papers, and Desterm for 80 col mode was perfect for my early internet use. I upgraded again to the 128DCR in 1989.
Long live the Commodore 128!.
P.S. The 128DCR differs from the flat C128 in that it has a full 64k of video memory, making it a 192k ram machine (not counting the drive buffer ram).
I had a C128 with 512k expansion ram, graphics ram expansion for Basic 8 coding, a 1541, 1571 and 1581 with the 1572 mouse. It got me all though college also and GEOS 128 was the bomb! I used Geo Publish to make our Commodore club newsletter and would output them as postscript and move them with Big Blue Reader to a floppy to print on laser at work! The best of times!!!!
GEOS 128 was amazing, and BASIC 7 was so good that I was able to start writing my own programs with it, instead of copying ones out of magazines.
Good call out on the 128 Geos, that thing was awesome I used it mainly for word processing and school work also. By the way there was a 128 Geos rom that I remember from the magazines back in the day, but never actually saw it in real life
I remember using my C128 to BBS and write stuff in Wordstar. After my C128 died I scrounged up a TRS80 model 2 with four 8" floppies.
Oh yeah. My C128 went into C64 mode only for games. I published a small press magazine using it (along with other computers - occasionally in C128 CP/M running WordStar), and wrote my first commercially-published software package, a C128-only 80 column mode BBS-focused terminal emulator. I also used apps like Paperback/Pocket Writer (again, 80 column mode) and as far as I was concerned this machine was an absolute beast, and C128 as C128 was the last great 8-bit. (Also you are correct, GEOS 128 was excellent and far better than the C64 version and I did use that a lot. That stayed in high-resolution all the time too.)
I prefer the struggle, it’s not like im watching this to learn, I’m here for the emotional rollercoaster of hardware diagnostics!
This video is hardly a "fiasco". Maybe from a repairing viewpoint, but as a video in itself I found it fun and entertaining to watch. There is something to be said watching failures that are actually part of the learning progression.
Hi. I think it's not a fiasco as you say, i learned lots of things.. And usually is when you have issues and you try to solve that you have value and experience, so i can say it's a total success! Thanks for your contribute!!
Errors, mistakes and screw ups are a good way to learn. When things just work right, we don't necessarily know why and we don't learn a thing. This is a good video for us to learn from. First lesson: read the manual! 😀 Just teasing.
SO many times I almost wiped my uncle's hard drive while figuring out DOS in my early teens, I can relate. Thank the hells for undelete back then lol
With all the fake masculinity these days: Reading the manual /first/ is what a /true/ man does, because sometimes doing it right the first time trumps effing around with your pride doing it wrong for hours until one finally opens the manual 😅
Read the manual but don't think it's gospel. Sometimes there are critical errors in them.
I feel like that’s especially true of computers of this era.
@@adampope5107 true. That’s when the student becomes aware. One of the best experiences ever to figure out that an errata is needed.
Whenever you test keyboards and type in the prompt, I always wish you’d type, “the quick brown fox jumps over the lazy dog”. That way you can text the whole alphabet keys at least. Just something I think of every time lol. Take it or leave it, you know I adore your videos. So proud that I can support you on Patreon. Keep it up, Adrian!
Heh that's not a great test IMHO, because most of the time I want to test the switches and typing each letter twice lightly can help identify switch bounce or dodge keys where it might work once but skip a letter.
It's a classic test dating all the way back from the telex machines, maybe even typewriters before that. Perhaps it doesn't find glitchy keys, but at least it finds the dead ones in the English alphabet.
I love the Commodore 128 content. That was my computer as a kid, so many afternoons playing games with friends and writing Basic and ASM programs
The sprite and drawing support was amazing on the 128, it was such a fun machine
I still have one of those C128DCR's. I found it in, of all places, a computer recycling warehouse. It was in a badly waterlogged commodore box, wrapped up in plastic, with the keyboard. Needless to say, I made it disappear from the warehouse. It works perfectly, except for the floppy drive. Once in a while it'll work, but it mostly whines and will not read a floppy. Bummer. Keep up the good work!!
Did you try to service that floppy drive? It might be something simple
I have. I think it's the bearings in the spindle motor that are bad. I also haven't tried taking it apart too much, not wanting to make it completely inoperable. It'd be nice to have a working 1571, as I have two other 1571's that no longer read either.
Thanks for featuring the mighty C128 again! Side notes: The SID on your model is a 8580R5 (it’s a 6581 on other motherboards), and that Z80 seems a 6 MHz model, although it runs at "half 4MHz", i.e. 4 MHz half of the time for an effective 2 MHz (check with oscilloscope) due to VIC-IIe bus access priority. I believe it could have been possible to run the Z80 at full 4 MHz when the VDC was in use instead of the VIC-IIe, but that would have probably required more logic. Note that CP/M mode was there just because the C64 CP/M cartridge was not working on the C128, and Commodore marketing wanted an extra check mark on the specs. Well, at least we had some extra fun with the Z80 in the C128!
The 8 bit dance party tempo was truckin today!
NTSC FOR LIFE! We livin’ in the 60 Hz land, baebee!
I remember using those pencil type erasers in typing class way back in the day.
**Adrian*** You being tripped by the harness and your 128D quirks just adds to the entertainment
In Germany back in the days, Mercedes Benz Diesel were very popular.
Well, we called it 128 Diesel.
This happens in software, too. You write some code, you write tests for it, you get test failures left and right…and after much struggle, it turns out that it's the _tests_ that aren't right, and the code being tested was working perfectly the whole time.
That's really the nice thing about 80's tech. It was built to last.
38:10 "... maybe I could have avoided so many of these Pitfalls..." Hey, I enjoyed all the times you ended up in Pitfall in this video!
Adrian your videos are truly awesome, even when everything goes wrong you still pull a rabbit out of the hat, when my projects often something is on fire or the mains power trips out.
Sometimes you win and sometimes you learn. Definitely a learning experience for ya!
I'm pretty sure I've seen those eraser 'pencils' at office / art supply stores in the past. There is also a version that works like a mechanical pencil (with replaceable eraser sticks), which I have at work, and yes, it REALLY comes in handy cleaning off edge connectors!
For sure, they’re incredibly easy to find at any Michael’s or Blick’s or other arts/crafts store! Super handy to have around.
Loved the video. You may have noted that, while it seemed pretty slow in 80 column mode in CP/M, it was still faster than in 40 columns. That's because it runs in FAST mode at 2MHz in 80 cooumn mode. The Z80 is technically 4MHz but limited to 2MHz due to its reliance on the CBM chips.
I know you said you could have avoided some pitfalls, but I enjoyed seeing Pitfall on the cartridge
My favorite thing about your work Adrian is how you'll gladly show us where you screw up, admit it, and then (assuming you know) show us how to avoid your pitfalls.
Avoiding Pitfall is as easy as selecting the right DIP switch settings =)
I have a very clean 128D that I was given around 20 years ago, without the keyboard. I tested it a long time ago with just a power-up, and it seemed fine. I've bought a German keyboard for it but I need to get the machine out again and *finally* test it for real. This video gives me a little push.
Such a great video. Everyone has skimmed over information only to find out later they missed something very important.
The 128DCR is pretty much the most unreliable machine Commodore has ever built.
I worked for a metalworking company in '90/'91 whose cutting machines were CP/M controlled.
The only way to get CP/M machines here in Germany at that time was with c128s.
The 128DCRs failed on average after about 3-4 months of continuous operation, while 2 old 128Ds (built in '85 + '86) were still running without any problems.
These were also the only two machines that lasted until the company switched to BSD-based computers in 1997.
However, storing DCRs for years was never a problem, our company had kept 20 in stock since 1990 to compensate for failing ones.
You may be too young for this memory, but your video reminds me of the Johnny Carson Show. There were times when he would do a monologue that would bomb, but it would end up being funnier than if all the jokes that were written were a hit. In other words, I enjoy you sharing your learning experience with us.
Your speaking of the difficulty of talking while also doing your testing, or preforming other tasks, during your video, while also acting as the producer and the director, reminds me of when I was a flying instructor on supersonic aircraft with the USAF in the 1970s. While flying, the expected procedure was, to talk about every action you were planning and accomplishing, while at the same time, flying manoeuvres at speeds often exceeding 8 miles a minute often in close formation). It became a more natural thing after a lot of practice, and thankfully, only had to be performed for the check pilot on our annual proficiency checks.
Loved the comment you said about avoiding the pitfalls. Best pun ever
I just took possession of an original case 128D (with the keyboard). It's of unknown working condition so this video gave me at least some ideas of what I might be up against.
The 128 is the 8 bit computer I always wanted back in the day but never managed to get one. Great to see this survivor still running well!
The Commodore 128 was three computers in one. A C64, a Z80 and a C128.
the floppy is another computer.
When the C128 came out the Z80 software was already out of date.
There were hardly any applications for the C128.
What was left was just the C64 compatibility mode.
No.
The plastic C128D is sometimes nicknamed C128 Diesel because of its rather noisy fan. :)
You are correct that there are normal C128 and 1571 motherboards inside the plastic C128D.
AFAIK no C128DCRs ever left the factory with a fan.
I noticed it does warm up a little but overall runs quite cool
The 'plastic' 128D using the same board as the 'flat' 128 was designed together with the 'flat' 128. The original board has a hole and some modifications specifically to allow for the original 128D (as per Bil Herd)
128DCR PSU tends to be very reliable and not go overvoltage, but note there exist at least 3 different PSUs. None are known to go overvoltage on failure. Seeing how yours still has the cutout for installing a fan, it is not the newest 'even more cost reduced' power supply. The biggest issue with the PSU is the PCB being rather brittle and easy to damage or break. Be really carefull when removing/reinstalling it.
I strongly suggest installing a low noise fan which can run from 5v (at a lower rpm). You don't need a lot of airflow, but just that little bit of airflow will help the power supply, and the nearby vic2 and vdc chips a lot.
Commodore made those machines with an expected lifespan of some 5 years... and for that you don't need the fan. But to make it last... that little fan really helps.
The mounting holes for the fan are non standard size, and I'd actually rather suggest to use some silicone glue or such to stick it in place, and at the same time provide some accoustic insulation between the fan and the case.
I actually validated the prototype of Sven's diag harnass for the 128, and can confirm it fully works with a DCR provided a longer cable for the cassette port connector. But keep in mind the 128DCR case leaves no room for the 'ears' of modern versions of that connector. That is a problem when testing a board while it is in its case.
Ah yes... CP/M actually is using a virtual terminal which is bandwidth limited, and pretty similar to using a 2400bps terminal. There is a way to increase its speed, but it won't ever be fast with CP/M... It can however be rather fast with a proper 'driver'. I have done quite a bit of development of software using it. During the last Commodore Users Europe 'online' meeting I did a 20 min presentation about one of my projects (OS128) which shows how fast VDC output can be, even with a multitasking OS. It has some '2d acceleration' functionality which is not used by the Commodore roms or CP/M, but when used properly can make a huge difference. An interesting and little known trick is to use rle compression when transferring data to it, and use its hardware fill capability to 'expand' the rle data. This saves bandwidth, and even when 'realtime' encoding the data, is often faster.
47:00 WTF? it is definitely a 8580 -- it sounds almost perfect (ofc it was composed for PAL and you play it in NTSC)
it's great to see you stepping up your diagnostic game since you've been full time! keep up the great vids!
was very cool to see cpm running on that thing! who knew. Great video as usual
A minor thing, but a couple of things I like about your channel (apart from the content of course) is 1) your short intro and 2) your ident, which fits into 3) it's not badly normalized audio-wise (so many horrible examples of idents blasting distorted with too low mic audio, it hurts)
Hi, Adrian. Have a merry Christmas and a happy new year to you and your family. Stay safe too. This video was a fun one thank you.
Loved the video!!! I have a 128D that I now want to work on and see how it is.
(6:45) I have an 128-D european model, with plastic case, (which I bought second hand in the early 90's).
This european model does have a 2.36" 'Panaflo' fan as standard. But it is EXTREMELY ULTRA-MEGA-NOISY, 😵💫 to the point that it was impossible to think and work (writing or programming) in front of the unit. It was infuriating.
I guess the metal case of the 'cheap' version helped to dissipate somewhat better the heat from the power supply, and that's probably why they decided to do without the fan, (further reducing costs, and saving US users unbearable noise in the process). 👋
That's just freakin' awesome that you were to get a 128DCR!! I can't believe your luck!! Congrats on your new acquisition!
Always interesting to see C=128 content, as it was pretty rare even when new. Have seen 128 only twice in my life in the 80's, once for the original flat 128 and another time for 128D. Only one time for Commodore 16 as well, but lots of Commodore 64's, including the one I had, C-64 C. Actually from the people I knew in the 80's, mine was the only C-model, all others had the original bread bin C-64.
I love that you have videos like this and don't cut out the struggles because I know I've done similar with my own projects even with just sticking to DOS/Win98 and newer
this would be completely different if that power supply had a fan. smoker's gunk everywhere. thanks for sharing.
I love your videos informative and totally honest. A treat for sure...
Merry Christmas happy holidays Adrian all the best and the tech bunker
That Christmas demo really brings back memories
My first machine back in the day and few years back reacquired another C128DCR. I had to fashion the same kind of keyboard adapter until I found a proper 128D keyboard years later
Well done man, do not be so hard on yourself.👍👍
I had one of these in my youth. My Sid chip kept dying on it. Other than that, it was a champ! Miss it. I also wired up the 80 column display myself to a new tv. Not bad for a 14 year old who just read the manual and hoped.
I thoroughly enjoy your troubleshooting videos. Please don't edit this out. This is a perfect real life example of how things can go wrong. Documentation is SO important when doing work like this.
I have found myself writing a repair diary and narrative on my repairs and things I noticed along the way.
Thanks Adrian.
Great video. I like the journey.
38:20 It's the same problem for streamers! Especially having to do live self tech support because there's always a problem, and its always a new problem.
Watching your missteps is more informative for a neophyte than a flawless presentation, your process of elimination is always a good watch!
i love your content. keep up your excellent work.
The keyboard adapter comes in handy for SX-64, too...even easier.
If you got the SX-keyboard cable, all it takes is a gender changer to use the C128D-Keyboard on SX64
I know, usually the SX cable is missing, but that´s a straight through, as far as I remember. So one could even get rid of the gender changer and use a standard 25P-cable with C128 KeyB. You´ll need a dremel though to make a 25-pin fit on SX
Enjoyable to watch
At 30:29 you note that it needs Rev 785260 but then 8 seconds later at 30:37 it shows you using still using Rev 588121. But you got it right on the second read LOL.
Best to show the mistakes, so we don’t make them, I learn a lot from your channels. Merry Xmas John(uk)
Well I for one will remember about the keyboard dongle issue. It's the errors and troubleshooting that I enjoy the most. Have a Merry Christmas!
Pitfall instead of diagnostics ROM saved my day! 🤣
Loved the video. Some actual broken c128 repairs would be awesome. Of course you have to have some broken c128s for that to happen :)
The C128D was my first home computer and I loved it and used it for over 5 years. Never had a single problem with it.
I remember seeing these in stores. My family was planning to get one, then saw the Amiga 500 and decided to go for that one instead. That was definitely the right decision in early 1989.
Your title describes my channel pretty well. :) I like to see all the details. If people don't want to see the detail, they can fast forward...
That IPA dispenser is fantastic, I need to get one.
Well, I tend to "get right to it" first and do the reading (if necessary) later if I should not manage to get something working, so I really understand you struggeling with both the test harness and the diagnostic rom😄
I miss Commodore, wish they were still around
Making MOS chips?
I had this exact machine back in college. It started getting glitchy and I scrapped it a little over two decades ago. One of my biggest regrets. I really wish I'd kept it and given it another chance.
You should take this show on the road, man. Showing us your mistakes is so very educational. I don't generally work Commodore hardware, but all systems tend to have little quirks listed in some dusty corner of the documentation, so RTFM (Read The Fine Manual) really does pay dividends. This video drove that home quite nicely.
You might try a breakout connector? That should allow you to try different combinations of jumpers to get where you need to be on the keyboard port.
I love these types of videos. We are all guilty of the same series of events for various reasons.
Hi, nice video. Seeing the 128DCR working still. My first own computer. BTW, a 25 pin SCSI cable is not necessarily 1:1 straight through. It’s only 8data lines some additional signals and a bunch of grounding for each signal as twisted pairs on good cables. I had a bunch of old scsi cables from my old servers and macs and needed to repurpose one a couple of years ago for som project that needed like 16 signals and 5 lines for power and ground and there wasn’t enough pairs there because almost half the pins were „shorted“ as a common ground and not just straight through - most likely to make the cable not too stiff with 25 connections.
I used to love the 128D's They were good little machines.
that black plastic bushing pushes flush to that bracket
I wonder if theres gonna be a channel in 20, 30, 40 years doing this kind of work with computers we use now. Imagine someone performing a resurrection on a threadripper or xeon they found in the trash for free.
Holy network TV credits Batman, those credits are too fast to be useful.
1 You should work out a standard set-up, so setting up no longer has to distract you while reading your instructions. 2 Find how you will read far enough in the instructions to not get a Raiders of the Lost Ark problem.
3 Happy Days
I think you should install a fan where the space for one is. Cooling would be great for the rare electronics inside.
That old Bank of America disk label is cool.
ahah I do the same all the time. Missing that important information and spending buckets of time on something! Nice video!
It's alright Adrian, I got you covered. It is the C128D... 'D' for Derelict
I chuckled a bit when you talked about all the 'pitfalls' in your testing of the computer (after the segment where you kept rebooting that cartrdidge) :)
I love the C128 even though yes, I mainly used it in C64 mode. I always wanted a D or DCR but yeah, never got one. Also, I think that if you were trying to avoid pitfalls I think you failed in more ways than one. ;) I also realised that I need to get myself an EEPROM programmer. That would be so handy for so many things, especially our C128 which has fallen into disrepair (keyboard wasn't working properly when we stored it so I guess an IC has gone bad and just needs replacing) so getting it tested would be nice.
Great video, Adrian. Merry Christmas./Gleðilig jól.
Yes, many Pitfalls. I think I counted four of them?
Great video as always Adrian. Have you ever consider making a video of your setup? aka what software you use in the modern PC of the basement and its periferals and the various gadgets or adapters for the diferents machines you fix?
great video
I bought one when I was 14 or 15 ;-) Nice to see one again.
I'm kind of shure it had a fan.
Adrian, that final screen from the demo... the only thing that could possibly make sense is that the SX-64 portable was called the Executive-64 in some regions. But 96 colors? Wow, there's a long distance between a 1 and a 9 on a keyboard. That's a hell of a typo. And let's not even talk about the Apple part.
The C128D was great for BBS'ing back in the day with 80 columns and software like DesTerm.
Back in the day I thought the C128D didn't make sense. With its price and the fact we knew the Amiga 500 was coming, I just skipped from the C64 to the Amiga. I did get to play on a friend's C128D but I never saw another one in real life, not even in the stores.
My thought as to making a keyboard adapter for the 128 to 128DCR... you can get right-angle pin headers - one row against the board then get a version with longer tails for thicker PCBs, then stagger the pads and stack that on top. Then on the other side a standard DB-25 connector. I'm sure it would be a simple layout exercise in most any PC board CAD app (like KiCAD)...
Pitfall being on that chip 3 times is pretty great foreshadowing.
Diagnostics are really only reliable if you know how they test what they test. For example, some ram tests may pass, while others on the same exact ram might not pass. Testing methodology matters.
I think my favorite old computer diagnostic tool was the "G-er." This was literally a DB-25 with a toggle switch on it and some pins jumpered inside. What it did was print upper case G's or if you flipped the toggle switch, lower case g's. This was a quick and dirty test to see if your dot matrix printer had a stuck pin or bad pin driver. G was particularly useful as it had descenders on the lower case g. Kind of like a printer loopback plug.
I once found an external keyboard at a flea market in the early 90s, but its having the spanish layout, and its still in the original bubblewrap, also I don't even have the D version, but better I have it than someone else :D
I had my fair share of C64, C128 and Amiga's over the years, and there was this sound demo, I made once a soundcopy of it and translated it to mp3 so I still enjoy it, but this was from one of the first amiga's, the soundchip was much better, when later models run this demo, it sounded worse, like the magic of the song was gone, the lead vocal in the song (instrumental of course) was in the original Amiga kinda vibrating, while the newer Amiga had a straight tone. Conclusion: other type of soundchip. Maybe this was also on c64/c128, later models, other sounds etc...
The fan was going to be there but was pulled at the very last moment to save money. Bil Herd talks about it in a video that the C128DCR was done, and he moved to working on the 264 line (plus/4, C16 & C116). He said it was much later that he found out they had removed the fan. Here is a SHORT video of a photo collage of me installing a fan (Noctua 60 X 25mm) into my C128DCR on May 19, 2022 and a video of what it looks like done and the fan start up and shut down. th-cam.com/users/shortsRgwsc672yjY?feature=share
Control ports fail when the keyboard lines are FUBAR because they share the ports on CIA 1. A well-known issue on the 64/128 is a joystick in port 1 causing phantom keypresses if wiggled.
Hi Adrian! I just ordered my first flat 128 so this video is very timely, informative and useful to me! I have the versa cart cartridge with all the diagnostic tools so I should be all set in case I need to troubleshoot any issues! I just received a 1571 drive and it seems to read a few of the floppies I have but being bought on eBay, I have no idea if they are any good or even erased!
What is the name of the donkey kong game you run, seems like the best SID tester!
Thanks for all the videos!
15:48 we used to use those in my typewriting class, we weren’t allowed to use Tippex (‘White-out’?)
The main processor in the C128 is actually a MOS 8502 ( en.wikipedia.org/wiki/MOS_Technology_8502 ). It's _almost_ the same as the MOS 6510 in a C64, but not _quite_ (much as the MOS 6510 was mostly the same as a MOS 6502). I'm curious if the C128 used that "P6" signal for anything.