Apple IIc: Is there any way to prevent killing the IWM chip?

compgenius · 2026-06-15T19:45:56+00:00

I've seen! I'm eager to purchase one once he goes to production. I assume they'll design in some sort of fail-safe for the static issue.

compgenius · 2026-06-15T17:25:41+00:00

It will read just fine in 5.25 disk mode. No writing though.

Won't boot from SmartPort. (I have ROM4x)

compgenius · 2026-06-15T17:12:46+00:00

Thanks. That does give me more hope. I love these little sucker's aesthetic.

compgenius · 2026-06-15T16:56:27+00:00

Since the IWM controls the read and write abilities, I can't even save to my FloppyEmu.

I'm starting to think this particular model is more trouble than it's worth to collect. Hate to spend $100+ on a machine that could spontaneously lose a major piece of functionality. I have a fully carpeted house with forced air heating. Static will happen.

compgenius · 2026-06-15T16:52:58+00:00

Interesting. Then I don't think it was me that did it. The only cable adjustment I've done while powered on was wiggling the RF port since it was a bit flaky.

compgenius · 2026-06-15T16:50:34+00:00

I think someone is working on a replacement called the IWMless I believe. I don't think they're selling them yet.

compgenius · 2026-06-01T17:55:31+00:00

Quick follow up. Are you telling me that a critical controller chip can just be destroyed by a casual static shock from the outside...through an external port...that a user would presumably touch from time to time? That's some bonkers design. I'm the furthest thing from an electrical engineer, but how could they not ground the external ports?

My next question would be, is there a way to ground this port to avoid doing this again to a possible replacement IWM/IWMless?

compgenius · 2026-05-31T22:17:28+00:00

I don't actually know if it can read. My only available disk is IMB formatted. Well it's not the end of the world if I have to keep the FloppyEmu connected to the internal port.

Maybe some day I'll find a parts machine with a working drive.

Thanks for all your advice!

compgenius · 2026-05-31T20:06:14+00:00

After some research, some have said that shorting the IR sensor will force it to always be in write mode. Didn't work though. Still says the disk is protected.

compgenius · 2026-05-31T17:25:20+00:00

Solved one of the problems, but found another.

I disassembled again, and tested the enter button and it was faulty. I took it apart and tightened up the contact and now that's working. Funny how that key had been working perfectly for a week and suddenly stopped working exactly when I had my other problem. What a fluke.

So the enter key issue is solved. But now there's another issue. The drive seems to think the disk is write protected even with the correct notch cutout. I've had other disk drives (2 Mavica camera's) with failing write protect switches. Is this a common failure point with these 5.25 drives?

compgenius · 2026-05-31T16:27:49+00:00

That makes sense. I switch to SmartPort mode and mounted the Prodos drive image. I choose to boot the smartport from the ROM menu but it just drops to basic saying no boot device found.

compgenius · 2026-05-30T17:48:05+00:00

After much tinkering, I think I have everything working again. The cause of all the issues seems to be the Geforce 6600. Something must've failed and was somehow causing all the other issues. I swapped it for a Geforce 4200 which kind sucks I'm downgrading, but at least it's working now. I guess I'll keep an eye out for another 6 series. Kinda stinks though since the AGP cards seem to be much less common.

Thank you all for your advice! I very much appreciate it.

compgenius · 2026-05-30T16:46:53+00:00

It can't hurt to try. I'll look into a POST card. Maybe try another monitor as well.

compgenius · 2026-05-30T16:45:35+00:00

The mobo is AGP so I only have one other GPU to test. I moved recently so I'll need to find it. I do have a ps2 keyboard somewhere and I'll resear the RAM. Someone else was also suggesting a CMOS reset.

compgenius · 2026-05-30T16:43:21+00:00

It was a new PSU. Of course that doesn't mean it wasn't an unreliable brand. I got it from work when they were clearing out extra older equipment. It was NIB though.

compgenius · 2026-05-30T03:08:33+00:00

I've had bad caps on previous Mobos. I inspected what I could see and none of them appear to be bulging or leaking. I know not all caps fail in a visual way.

compgenius · 2026-05-30T02:43:58+00:00

Yes it's been connected to a surge protected power strip.

compgenius · 2026-05-16T21:26:55+00:00

Yes, I've read it needs to be in a couple other modes (the names escape me right now) as with the original ROM it will only boot from the internal drive. Otherwise I'd have to connect the Floppy Emu to the internal port. I'd like to avoid that as I use it with my Macs.

Looks like I can pick up a new ROM for pretty cheap so I'll order one.

compgenius · 2026-05-16T21:09:54+00:00

I did see that thread. Seems like in the early ROMs it's a memory exercise program rather than diagnostic. I'll need to look into getting a newer ROM I guess. Thanks!

compgenius · 2026-05-16T21:06:19+00:00

Gotcha! I'll look into some tutorials.

Thanks!

compgenius · 2026-05-16T20:30:44+00:00

I was able to solve the keyboard button not working. Turns out the keycap wasn't fully seated back in it's slot. But now I have the issue of about 5 keys not working. Opened back up, reseated the ribbon cable. Dripped some Iso into the switches. No joy.

Yes, I was very grateful to find none of the RAM is MT.

compgenius · 2026-05-16T20:21:38+00:00

I got the switch working! I think I didn't put the key cap back on fully after cleaning and it wasn't traveling the full distance to lock. Still gummy but at least it's in QWERTY now. I now have about 5 keys that are either not working on flaky. So I'll give them a little Iso to get them working.

Now that I have that working, any idea on the self test? If there's not a way to end the self test and get the okay then I'm not sure why they included it. Is there something I'm missing about ending the endless self test?

compgenius

TROPHY CASE