What's keeping this Apple IIc from working?

Today it's time to troubleshoot and fix a dead Apple IIc computer!

--- Time Code Jumps

0:52 - Intro to the Apple IIc
4:18 - Powering the machine up for the first time
8:40 - Starting the troubleshooting
11:42 - Dealing with rusty case screws
11:57 - More troubleshooting with the oscilloscope
29:18 - Upgrading the Apple IIc ROM from ROM 255 to ROM 0
32:14 - Using a Macintosh mouse on a IIc
33:59 - Figuring out why the machine doesn't always boot

--- Video Links

IZ8DWF's channel: (he always gives me great advice on fixing these old machines)

Apple IIc ROM 0 upgrade:

65C02 information:

Apple IIc Schematics:

4164 DRAM Datasheet:

DRAM list from:

Apple II Technical Manual:

Apple II ROM Images: (including the Apple IIc ROM I used)

--- Tools

Deoxit D5:

Jonard Tools EX-2 Chip Extractor:

Wiha Chip Lifter:

O-Ring Pick Set: (I use these to lift chips off boards)

Elenco Electronics LP-560 Logic Probe:

Hakko FR301 Desoldering Iron:

Rigol DS1054Z Four Channel Oscilloscope:

Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier:

TL866II Plus Chip Tester and EPROM programmer: (The MiniPro)

TS100 Soldering Iron:

EEVBlog 121GW Multimeter:

DSLogic Basic Logic Analyzer:

Magnetic Screw Holder:

Universal ZIP sockets: (clones, used on my ZIF-64 test machine)

RetroTink 2X Upconverter: (to hook up something like a C64 to HDMI)

Plato (Clone) Side Cutters: (order five)

Heat Sinks:

Little squeezy bottles: (available elsewhere too)

--- Links

My GitHub repository:

Commodore Computer Club (of Portland, Oregon and Vancouver, Washington)

Tivoo Pixel Art Display seen in my videos:

--- C64 Stuff

JaffyDOS:

C64 Test Harness I use:

C64 Homebrew cartridge PCB: (used for the DeadTest / Diag Cart I use)

EasyFlash 3 Multi-Cart:

--- Instructional videos

My video on damage-free chip removal:

--- Music

Francis Preve - Wild Pogo
Unicorn Heads - Telepathic Drive

Intro music by:
Nathan Divino
@itsnathandivino

Outro Music:
Attribution 4.0 International (CC BY 4.0)

--- Image Credits

Apple IIc pictures (used on Thumbnail and in video):

Mac IIx Picture:

Apple IIgs Picture:

Mac IIsi Picture:

[rossmanngroup]

My girlfriend keeps talking about wanting a new Macbook. It is incredibly tempting to buy her one of these for her birthday so I can film the reaction.

[amycollins]

The Apple IIc is probably the most beautiful 8-bit machine out there. It made my day to see this one rescued by Adrian to operational status rather than becoming purely a parts machine or worse ending up in the landfill.

[PeachIceCreamy]

Adrian, your channel is big but it should be bigger. These kinds of videos are so great to watch, not only for entertainment, but to learn a lot of the things others had to do through experience without risking damaging anything in our own hands. I’m an electronics student, and these kinds of videos teach me a lot. Thank you, and keep doing these!

[DropDeadFrederick]

One of the computer's bugs escaped at 6:12. :D

[eden]

Hey Adrian, prepare for a bump in subs care of Louis Rossmann. On another note, I’m in Portland too and love working on this vintage equipment! I have an original Macintosh on my bench for a recap right now in fact and did an SE30 a couple months ago (connector replacements).

[MBDB]

Thanks to Adrian Black, 8-Bit Guy, and Retro Recipes, I have had great success repairing, upgrading and modifying all my Commodore and Apple computers. Thank for being so thorough and informative. Long live the Basement! 😁👍

[godmonkeyjr]

Another option to the old gift card is to learn to play guitar. You'll always have picks around. Except when you actually need them to play the guitar. Another bonus if you go acoustic you'll usually be able to find one in the guitar. Love the videos!

[brad]

I love the fact you care about the little things like rusty screws and de-yellowing the plastic. You do things properly, love it :-)

[devttyUSB]

Great diagnosis, again! You're much like the automotive channels i like to follow, very methodological in finding the faults. It soothes the mind and saves old rare computers. You're a pro, not an amateur. Keep bangin', Adrian!

[screamengine]

I got a IIc with the same symptoms and I assumed it might be ram. This is the first video out there to really explain what's possibly happening. I'll be sure to comment again when I finally crack it open to check things out. It has to be said that your presentation style is awesome and universal for beginners and experts alike. Subbed!

[timharig]

29:24 That actually makes perfect sense if the version byte at 64447 was intended to be read as signed. The two's compliment of 255 for an 8-bit value would be -1.

It may be that they were using negative version numbers to indicate pre-release versions the way that version numbers less than one are used today.

So the version numbers ARE in proper order: -1, 0, 1, 3, 4.

[Natomon]

This was my first computer. I picked it up at Goodwill. I was astonished at just how easy it was to disassemble. Good memories. The warmstart vs coldstart behavior you're describing actually explains a lot. Back in the day 13-year-old me without any manuals or the internet didn't know how to get into basic from the initial boot prompt. So my solution was to rapidly power cycle to get there. This was also my solution for a later II/GS I acquired.

[SofaKingWeTodEd]

the apple IIc was the first computer i ever used, i remember playing oregon trail on it all the time when i was little.

[tbnshci]

Cool little computer, even today. Love the matching little monitor and mouse that came with it. Great channel Adrian. Between you, 12voltvids, and joes classic games, I think I can learn to troubleshoot and fix almost anything. Thx!

[ghostbuddy]

Louis Rossman sent me here, he was right. Great video!

[zman]

Never owned these computers from the 80's other than the Atari 2600. But watching your troubleshooting videos makes me want to find one buried in a box at the local flea market & try to bring it back to life. Thanks for the troubleshooting vid!

[Felice_Enellen]

I _like_ the up-facing sticky tape trick to check for contact, but you might want to do that with a small spacer under the tape so you know you have reliable clearance. Cases flex/expand/contract, after all.

[GXR]

Wow, this just taught me why I would see "ghosts" of previous sessions when I would flip the power on my school's IIC quickly!!!!

[archelonprime]

Just mentioning Louis Rossmann got a like from me, LOL! Although I never opened a IIc, I do have fond memories of them during my high school days. And kudos for re-using the TRS-80 Model III badge/label on your monitor!

[lwvmobile]

These are the computers we had when I was in Elementary school. Have tons of good memories playing games on these in kindergarten, first, second, third grade or so. After then, I think our school upgraded to Macintosh computers, but those were only in the school library. Sadly, teachers would never schedule our class to go. I remember using those Macintosh computers two or three times ever. The Apple //c computers were in every classroom, at least 4 of them.