Mysterious Commodore 64 Repair & Chip Socketing | see description
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- เผยแพร่เมื่อ 12 ก.พ. 2018
- 🙏 MY PATREON: / perifractic
🎶 See below for the Ringtone, T-shirts, Recipe Ingredients & more!
🍟 ON TODAY'S MENU: What evil could give Alice spots! After "seeing spots" when connecting a joystick (which is usually a CIA error) I try to fix the issue. I had been seeing garbled characters or issues with colour blocks on the Commodore 64 BASIC screen and certain games, so here we attempt to get to the bottom of it, and socket some chips along the way. Could it be the CIA chips, the Color RAM, or something else? A dead test cartridge may help. Will it work?...
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THE COOKWEAR (T-SHIRTS)
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🕹️ Replacement chips: www.retroleum.co.uk
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Thanks for watching! What's the weirdest fault you've had? Let me know below!
I know that the lack of a loopback cable can also cause the U1/U2 errors, but that's usually just U2. As connecting the joystick was causing the Colour RAM issue, and that is usually a CIA error, I decided to switch them anyway. Your friend in retro, Chris aka ԹҽɾíƒɾɑϲԵíϲ
i know it is kinda off topic but does anyone know of a good website to stream new series online?
Hi, if you run Diagc64 or C64Diag you need special cable adapter hooked up to the user port and joystick port and keyboard port. If you don‘t do this you aleays gets bad U1 and U2 chips. Just look this specs up in the internet. theyvare really easy to build.
Fossi Soft Thanks! You're not wrong, as others have pointed out. Check out my description 😉
I have the same Error on U1 with all of the feedback loop cables installed I wrote a small piece of code to find the problem, what I found was that in one direction or position of the joystick would slow the processor down, that is a timing fault within the 6526 CIA chip registers still looking into that but it is a problem with the 86 series more common than not. I have a 93 series chip coming at the time of this post so we will see. BTW I have seen worse Color Ram corruption. the color roms do fail caused by the SID... Love your channel I'm going to start my own youtube channel here soon you guys could probably use my help 40+ years of electronics and system designs sure why not. Your doing a great job!
Thanks for the info. Interesting! Let me know if that works and good luck with your new channel!
Nice video. I like your Jan Beta impression. I wasn't aware of your channel. Glad I found it -- now I have to play catch-up. Subbed.
MindFlareRetro Hi, it's Jan Beta. Just kidding! Pleasure to have you on board! Feel free to spread the word about my channel. It really helps. Thanks again!
I've already tweeted a link to your channel. All the usual retro computer folks on Twitter will be happy to have a new YT channel to watch. I have a channel, as well, if you are interested in more Commodore repair fun. Are you on Twitter, as well? I am @MindFlareRetro. There's a great international group of people to chat with.
MindFlareRetro Great. Thank you! Yes I am @chrisimpsonline and I already follow you 😉
Oh my gosh. Thanks. I hope I'm following back. I will check.
Another very enjoyable odyssey into retro repairs. Thank you!
Thank you so much! That means a lot to me. 👍🕹️
Excellent repair work sir! I just found this channel. Subbed.
BTW, found your channel via 8-bit guy. Subbed.
Welcome! 👍🕹️
Nice work. I had a job getting my NES going. The 72 pin socket wasn't the problem, someone had been trying to fix it and broke it. They cut the IRQ line on the board and rejoined it but didn't notice they also cut the adjacent line. I soldered a wire in to rejoin it and my game booted. All it cost me was $8 at the thrift store and a little work. I'd say that attempted repair was due to the 72 pin socket and the repairer mistakenly thinking the IRQ line had anything to do with it.
Well done! 👍🕹️
Nice video. You did a great job desoldering and soldering in the socket. I appreciated how you captioned the part where you removed the chip with the chip puller to use *gentle* pressure. I learned the hard way on one of my first desoldering repairs that if you have to pull it out with too much pressure you will likely lift a trace or a pad. I did exactly that and ruined a board. Well when my skills improved I actually repaired it but still it was a hard lesson to learn. Now I make sure those suckers practically fall out on their own after desoldering. ;-)
Racer X Wise words.
4:48 When you ask your parents for Jan Beta.
Parents: we have Jan Beta at home.
Jan Beta at home:
I always prefered wick/braid when desoldering chips like that (unless I have a powered desoldering gun that is). I've seen those suckers suck the pad right off the board if it's in bad shape already. I did get irritated at desoldering stuff and eventually built myself a solder pot. Use kapton tape to cover all the surrounding pins, set the board on the pot, and pull the chip out of the holes, then drop the new chip into place. It does require you to ensure all the pins on the new chip are nice and straight and lined up with the holes or it won't drop in, and don't want to leave the board on the pot for too long.
i suggest to check the traces and pins for the ports, every port seems to give an error. great video
just found your channel, fantastic vids man, definitely curious what the issue is with that error.
Thank you so much! Me too! 👍🕹️
since you do retro repair ... this is just a suggestion.. but when desoldering its a good idea to heat all the joints and add a bit of leaded solder to each joint before desoldering... it helps with the melting and flowing of the solder...
It is a good advice, but he fears lead, so he won't do it. Theoretical: Would adding (nearly) pure lead to the old solder lower the melting point even lower? Since you are sucking it away anyway, it should not cause trouble for the new solder joints etc
I use this smd flux (liquid, like used in the industries). It is pretty cool with solder wick and soldering in general.
In order to make full use of the dead test, you need to get a hold of a harness. It consists of loopbacks for the User port, the cassette port, serial port, joystick ports and the keyboard connector. This is the reason the test says the 2 CIA's are reading bad.
Yeah see pinned comment 😉
If you want protection against lead you should wear properly treated working gloves, lead penetrates the skin quite easily so touching it is enough to transfer it into your body. Ventilation is still good because of alcohol/flux fumes and some other fumes which can be formed are still bad to get into the lungs.
Someone should send this guy the DIY Rubbermade air filter video: th-cam.com/video/JdrFsuAcm48/w-d-xo.html
Mr. Ward uses home stovetop hood filter screens. Works great, under a hundred bucks. Kills the smell of fluxing, too, along with lead particles in the air.
To the contrary, lead does not penetrate the skin easily. The main route of possible exposure in this scenario would be ingestion. In other words, don't suck on the solder, clean your work area and tools regularly, wash your hands (and/or use disposable gloves), and be mindful when children are present.
Ventilation is of course a good idea. My understanding is that while lead doesn't readily vaporize and is little cause for concern, the flux fumes are an irritant.
And don't bite your fingernails...
love your chip hammer; lookig for long-weight and checkered paint to follow on sub :)
Nice video. Those diag tests are not the brightest. Could be any link in the chain. Well done with the desolder, I never could get on with those manual desoldering pumps!
Something I've found that works quite well for cleanly sucking the solder out of the holes is to stand the board up on edge with a few small clamps, press the tip of the soldering iron to the leg of the pin on the chip side of the board, and suck the solder from the solder side of the board. That allows me to keep the sucker firmly down over the hole while not having to remove heat from the pin. Until I can afford a desoldering pump, that seems to work best. And before you pull the chip out, you ALWAYS want to wiggle each and every pin on the back side of the board with a tweezers or needle nose pliers to make sure they have released from the through hole as much as possible. Even if they all seem to have fully released, there may still be solder binding them to the stop side of the board. Don't just yank the chip out; use a flathead screwdriver to very gently pry the thing up while observing all the pins. If you see any trace or through hole rim start to pull up, stop immediately and use the soldering iron to melt the solder and push the trace back down to the board to minimize the damage. While it's easy to repair a broken pin on a chip, it's a bitch to repair a lifted trace.
By the way, the diagnostic cartridge is always going to show a bad U1 and U2, as well as other things, when you don't have the full testing cable installed that wires all the ports together. There's a schematic for how to build one. For the portion that plugs into the keyboard pin header, you can make something out of an old IDE ribbon cable.
Thanks for the tips. Thankfully I found a good value desoldering vacuum and use it in later videos. Link is in related Description. And in this Description, I acknowledge the U1 U2 discovery 😉🕹️
The past many months I've been going through all my C64s and 1541s to clean them all and make repairs where necessary, so I've been doing a lot with the diagnostic cartridge, pulling chips, installing sockets, and everything. I have two bad boards that are just baffling me because I can't find the fault. One of them, I replaced _every_ chip and the thing still crashes after about a minute of being powered up.
Got some heat sinks on the hottest chips? The timing implies heat build up or a coincidentally heat sensitive replacement chip... 🤔
This is a board that died on me about 20 year ago that I'm trying to resurrect (PCB# 250466, the long board with the two RAM chips). I did find one hot RAM chip that I pulled and replaced, and that at least got it to turn on. It does seem to be a heat issue since it only works for 30 seconds to a minute before screen garbage starts and it eventually crashes, hardly long enough for anything to get warm, and that's whether I use the diagnostic cartridge or boot it to the BASIC prompt. The original PLA and SID are fried so I'm borrowing a good working PLA (leaving the SID out for now since it's not necessary, but inserting a good working SID makes no improvement). All the other big chips test good in another working computer I'm using for testing regardless of lack of heat sinks, and putting all the big chips from the working computer into this board gets the exact same symptoms (same with another set of working chips). And the original VIC is in use in another computer, so I'm having to use a working spare.
One by one I've pulled all the small chips, socketed their places, and tried putting in salvage chips, and the symptom remains the same. The only chip I can't replace is the 8701 timing chip because this is the only board of this type I have so I don't have a spare 8701, and they don't exist in my salvage electronics junk bin. I've even tried heating up the board significantly with a heat gun in sections to try to narrow down where there's a thermal issue, but the thing always worked for that 30-60 second window before crashing, and once it crashed it stayed crashed just the same as when I started testing it cold again. Once it's crashed it has to sit for an hour or so before it'll work again.
Getting very in depth, testing with the oscilloscope shows the address lines A12, A13, A14, & A15 with a nice data pulse when it's working, and then they all go flatlined at 5V when the thing dies. Those address lines are used by the U13 multiplexer, PLA, MPU, resistor pack RP4, and the cartridge port, with only the A12 going to the kernal and BASIC ROM. What's strange is that when I pull the PLA out, the data pulse returns on those address lines, but on the working test board it's just the opposite: the address lines are flatlined at 5V with no PLA, and they show the data pulse with the PLA installed. It's all the same with other working PLA chips as well.
One thing I have yet to do is icing various parts of the board after the crash to see if I can get it cold and expedite it working again to point towards where the problem is, if it is in fact a heat expansion issue.
Yep I was going to recommend icing. Also Retroleum.co.uk to replace the 8701. Let me know! 👍🕹️
Just found your channel and subbed, weirdest fault i've had is the Saga Master system Mk1 I’m working on at the moment, graphical glitch and i've changed all the usual suspects and its still glitching.
Thanks for the sub! Good luck with your fault; these machines work in mysterious ways...
Alright, that's really weird but in a good way. Having never heard of Alice in Videoland (the game) I poked at TH-cam and found a Swedish synthpop band named Alice in Videoland. Good band, in my opinion that is. But totally unexpected. :D
Why does this ONLY have 2k views???
Hahaha thanks. I've only been going a few months. Feel free to share 😉👍🕹️
Great Video.
I love the heatsinks!!! What size are they ad where di you get them?
I head that the thermal tape is not as good as the thermal poxy for them. Your thoughts?
Thanks! Check out retroleum.co.uk Thermal tape seems to work fine. They get very hot!
I just run the same diagnostic tool and my 100% working C64 reported bad U1. I have to get that C64 diagnostic cable set.
TheMr Jamu me too! Or make one
did you checked the tracks with the magnifier?, it can be as simple as a bad track to hole connection, maybe one oxidated under the solder mask, just in a tiny part, so, interrupting the signal..
Thanks. See description 😉🕹️
I see you video is 2 years old, still excellent btw, any updates on this issue?
From what I can remember it was the color ram.
as mentioned in one of your other vids when i repaired my c64c i replaced the 6526 with 8520 from an a500 - worked fine. only difference between the two is the 6526 runs at 1mhz where the 8520 runs at 2mhz (not its not overclocked), the 64 just runs the 8520 at 1mhz. also subbed as well, great content and great presentation.
Great tips and thank you so much! 👍🕹️
Did you try the chip again to make sure it wasn't a solder issue?
Sure did!
Just browsing through again. Had to comment on the soldering portion of the video.
I'm more fond of wicking than using a sucker. Reason being is when working on old boards, I've ran into rather nasty incidents where the sucker actually took contact pads off of the board. Wicking is more delicate in this fashion, which definitely matters to retro boards. Simply flux the wick and press it to the desired removal location, and heat with the tip of your gun, dragging the wick very gently across the contact point.. Heated flux and copper wick draws solder towards it like a magnet, into the wick, and offers the added bonus of lowering the risk of contact pad damage.
You're not wrong! It's happened to me too. Good advice! 👍🕹️
Would I jinx it if it would be the issue with the onboard cartridge slot? Like oxidation on the PCB as that happens from time to time and is very picky about its occurrences ( the life saving breath for old cartridge based electronics thing ;) ) Based on same way that Easyflash diagnostics interfaces with The Board .
Bad trace or supply rail which may be the real issue. I take it that you re-capped it so that you eliminated the capacitors, did you do the ceramic ones as well? They can, as rare as it is for ceramic's, go bad, often down to the manufacturing process.
Great video. Great tip to put the dip socket in. Time saving in the Future ☺.
Do u have any suggestions on any good budget soldering irons for getting started? I am guessing the one you use is for a pro and ££ lol
Thanks! I do have a cheaper one. It's not budget, but it's the only one I'd recommend really. perifractic.com/tools 👍🕹
@@RetroRecipes is it the
Holife Soldering Iron Station?
@@korosu2203 No it's a particular Hakko one. Just click the top-left link at perifractic.com/tools to be taken to your local seller
@@RetroRecipes Thanx again. Really appreciate your time.
Just learned about the C64 power unit blowing chips. Think this must be the cause of my problem, since I used the same power unit on both C64's and have the same fault. you live and learn I guess lol
Do you have a list or can link me to a list of all the sockets required to fully socket a c64? I'm not sure of the pitch and spacing. Thanks for all the great info and videos!
Best thing is to buy an assortment box on Amazon. They're all pretty standard. 👍🕹️
@@RetroRecipes Thank you. I ordered a bunch off Ali Express. Amazon Canada wanted too much lol
What is the flux used to clean the iron tip???
See the tools I use at retrorecip.es/tools 👍🕹️
Music at begining ? :)
Are you using an original power supply? I had a commodore 64 with a power supply that was starting to go and it produced a lot of the problems that you were seeing including garbled characters do to a damaged chip caused by the power supply, and I also found that a lot of the peripheral ports that are controlled by u1 and U2 are some of the first things to go, if you're using an original power supply change it and see if that helps
Hey, where's the link to the tip tinner?
See perifractic.com in the shop 👍🕹️
Do you use dual-wipe sockets to match what C= used to use, or is it just what you happen to have on hand? Generally in rework like this I prefer to use machined-pin sockets as they will stand up to future oxidation better, and they're also easier to remove and reinsert devices - dual wipes that have been seated for a few years can really cling to those pins, especially if the pins were tinned as the leaves of the socket will bite into the PbSn coating. The only thing to "beware" of when using machined sockets being, if you are reinserting desoldered chips, you do need to clean the pins up well.
It's just what I happened to have 😊🕹️
fair enough :) interesting channel btw. I've been watching what's new and hip in the world of C= 8-bit resto because I'm digging all my 8-bits out of storage to test, catalog and mothball properly (lewinedwards.com/wp-content/uploads/2018/10/2871936426013663583.jpg is a tiny sliver of what I have queued up to clean and fix). Biggest resto issue I have right now is the damn keyboard springs - I know people swear by vinegar to get the rust off these, but I don't have great results with that and in fact it seems to promote worse rust. Right now I'm agitating them in vinegar and soaking for 3-4 hours to remove the majority of the rust, then I drain and rinse with water until no vinegar scent is detectable, followed by air drying, then an IPA bath with vigorous agitation which removes a lot of rust that seems to re-form during the air dry period. But they still require manual rubbing with a paper towel and I'm not at all satisfied with the final result.
Wow that's a nice collection! If you've tried all that I'd try sourcing replacements. There must be a standard type out there in China that you can order and that fits... 🤔 Get some exact measurements and look on eBay... Good luck!
Believe me that's the tip of the iceberg. I have 20-30 VICs, some C16s and Plus/4s, maybe 10 C64s, and four C128s.. and that's not even getting started on the peripherals and the non-C= stuff. I can't seem to find any of my C64Cs though, and am actually going to fly up to my old house in NY to see if I left them in the attic or garage. Weirdly, the C128s seem to have weathered time the best - all of them work A-OK whereas most of the VICs and C64s are no-go. And yes that's a great idea on sourcing the springs. I'll measure them and see what I can find. All kinds of weirdo industrial stuff like that on eBay (not to mention alibaba etc). And with the number of machines I have in stock, it makes sense for me to order a thousand springs and get a decent quantity price break.
Good luck. Maybe it was just because the C128s are the "newest" 😉🕹️
And nobody's gonna address where such a pristine C64 board came from? IT LOOKS NEW!
Let me address it 😉 th-cam.com/video/XrTmwooQ298/w-d-xo.html
I will soon be making a board that allows me to switch between NTSC and PAL on my 250407-RevA. Not on-the-fly - but before power-up. I will have both VICII chips, both crystals, both c70 capacitors - so why not. I know I need to completely disconnect inputs and outputs from the VICII not in use. I remember something (from the 80's) about don't put signal to unpowered TTL devices. I am presently just learning all that I can about the VICII / RF modulator disconnection, luma / chroma crosstalk. etc. I have grown tired of waiting for someone else to tackle this, I'll just have to do it myself. I would gladly take any info anyone has on C64 IEEE488 / GPIB communication. This is not related to VICII chip project, but rather my bench multimeter; I want it to SPEAK. It is a Keithley 2001 and has GPIB port. I think the C64 is more than capable of this integration and task and I think it's magic voice module needs some work to do.
Does this help you? www.fascinationsoftware.com/FS/html/Plus4-videoswitch.html It's very old (there are few new ideas) and by my friend Richard Goedeken. One of my Patreons recently asked me to make it into a video; I've had a lot of similar requests. Happy to collaborate. Feel free to email me. See description donation link. 👍
Perifractic's Retro Recipes !
Hi again, would you like to discuss your board idea at www.lemon64.com/forum/viewtopic.php?p=831202#831202 ? I'd love to promote it for you and do an install video as soon as you have it. RSVP. Your friend in retro, Chris aka ԹҽɾíƒɾɑϲԵíϲ
Hi, I wonder if it might be some power issue of some kind so those chips does not work properly cause they got not enough current. maybe a capacitor that broke or almost broke?
See description 👍🕹️
@@RetroRecipes I C 👍
I can tell you're using that horrible lead-free solder, since all your new solder joins look dirty and dull. Still excellent job overall :D
True. I found a better brand though. I don't want to take the 1% risk that it does cause health issues, so I can rescue retro machines when I'm in my 100s!
I get why people use it, but I really hate the stuff. It's just harder to work with. If I could find a decent lead free solder I would use it but all the ones I've tired are just the same - dirty/dull joints and more difficult to work with.
Terry Beardmore yeah it has a higher melting point so it's not as good for people using cheap standalone soldering irons. Those with proper soldering stations should be ok though
AndehX oh yeah I agree. I can work with it but I just find it more difficult and somewhat of an unnecessary hindrance to working even with my decent equipment. It's definitely a lot better than it used to be just a few years ago.
Is it possible that not having the test harnesses hooked up is causing the issues with the U1, and U2 testing results? It's been a while since I've had mine hooked up to check a board. Perhaps someone else will remember?
+Jeff Ledger You're not wrong. Check the video description 😉
That is absolutely correct. If you don't have the full test harness the Commodore C64 diagnostic cart will not give you correct results for some tests.
Racer X Thanks for confirming.
If you haven't fixed it yet, my guess is the VIC chip (U19).
Edit: i'm almost sure it's the VIC chip.
It is the vic 100%.
Capacitor replacement? Done that yet? I mean, if you're plugging components in and the new drain is suddenly causing errors...
That's super weird.
See description for the resolution 😊
8:07 lead fumes aren't the issue; flux fumes are.
My source (PDF): www.google.com/url?sa=t&source=web&rct=j&url=www.cmu.edu/ehs/Laboratory-Safety/chemical-safety/documents/Lead%2520Soldering%2520Safety%2520Guidelines.pdf&ved=2ahUKEwi3yeuis9zcAhXHhlQKHZRBAk4QFjAIegQIBhAB&usg=AOvVaw0sYdp6EwDFwYrJWHCoh4sy
That's just regular foam, the static dissipative stuff is pink. So your chips aren't actually known good anymore.
I thought DIP meant dual inline package.
You must have a harness with a diagnostici test.
you should get a c64 reloaded motherboard.
Have you been reading my tweets today! twitter.com/chrisimpsonline/status/1071584810420756480?s=19
Did you try using joysticks?
Yes, same result but they work
May I suggest that you edit out the part where you remove u1 and u2 just to avoid others making the same mistake? Removing chips that are in fact working is not a good idea
Verrrrry old video and TH-cam offers no “edit after you upload” option. I will say that you are the 1st to mention this. It doesn’t mean you are wrong, but a lot of people enjoy and find it very educational to watch the process of discovery, including any blind alleys that one goes down. So I think I’ll leave it as it is. But thanks for your feedback.
@@RetroRecipes yes, I realised that after posting the comment. Makes sense
Ghost in the machine
I use a solder pot for getting big chips out. Yes I make bridges if I don’t cover other pins (thank god for Kapton tape) but I hate solder suckers, sometimes they miss a tiny blob of solder in the through hole and you have to hunt down what pin is still partially soldered if you can’t see it.
Can you clarify how the "solder pot" works?
I suck at soldering
You need a desoldering iron it's so much easier
See later videos 😉
You only really need to play Alice about once every 5 years to remind yourself how bloody awful it is! 😂
It's more a nice memory of picking out the budget game with my parents, and the excitement of loading it 😊🕹️
I worked in a computer shop at the time of release. It was £14.95 in the UK, long overdue and a huge disappointment. I don't think we sold a single copy.
I want to say we picked it up for about £4.99 at WH Smith. I got Time Traveler too from the budget shelf. Very rare, and strangely atmospheric.
For that price it's worth it for the historical value :)
Without Testharness, CIA und SID are always bad. I have no idea why SID needs the Test Harness though.
Because it handles analog controller input (paddles, mouse)
@@christianlarsen1070 Makes sense. This is something, I never used. Thanks!
I think, your solder sucker sucks. I am using the soldapullt for over 20 years now. It really sucks a lot and I like it. I have one like yours, too. But that doesn't really suck. I mean, it is not so great.
"Colour" isn't only just British. It simply also is correct!
Fortnut on zx spectrum is EZ
😂
K you allreddy wear of an commodore 486-33c?
😂😂
Doesn't the SID work with the CIAs to do the joystick or something? I have a vague recollection they are connected somehow. It's likely possible for chips to mostly work eg. for the SID to produce sound but for it's more obscure functions to not work exactly correctly, eg. stuck bits, etc.
The SID is used to handle analogue devices lige paddles. It is reported as bad because there isn’t a test harness connected to the controller ports
Would you marry me?
I'd have to check with the current Mr/s Perifractic... ¯\_(ツ)_/¯