bigmessowires sent me a second ROMinator containing the stock IIci ROM image (thanks!) to experiment with. On the mostly-working board, it boots just as well as with the onboard ROMs. From talking to bigmessowires a bit, he noted that the way the ROMinator custom image may still be exercising...
Actually, I just tried the ROMinator in the good board with some RAM, and I still get nothing. It gets to the question mark floppy icon no problem with the onboard ROM. Maybe the ROMinator is bad?
I got that other board recapped, and it's in much better shape than the first! I got to do some experiments. With the onboard ROM and no RAM installed, it gives the boot chime followed quickly by the sad arpeggio. With the ROMinator, it gives silence. So that suggests that, if it isn't the VIA...
I poked around a bit more last night, removing the VIA and checking continuity. There wasn't any goo trapped underneath, and all of the pins appear to be connected appropriately according to the Bomarc schematics, with one minor exception: Bomarc shows pin 23 (IRQ) having a 1K pull-up resistor...
Yeah, W1 is open, and it tests open with the multimeter so there isn't any short. I walked through the first stage of ROM startup in the MAME debugger's IIci emulation, and while an instruction is different here and there, the detection routines still look close enough that I was able to follow...
The onboard ROMs were definitely toast—I snipped them out and a bunch of the pins were just rust and crumbled away when I went to cut them. The SIMM slot however seems to be OK; the address lines all look good going to the CPU, and I didn't pick up any shorts across the lines. If it is failing...
I had some time again to look at my IIci board again. I rechecked the continuity from the RAM SIMMs to the F245s, the CPU, and the MDU and so far the traces in that region still all look fine. I did manage to find a broken trace in the startup circuit: pins 3 and 4 on UE13 are supposed to be...
Just to experiment, I tried putting a few sets of RAM SIMMs into Bank A since I had those soldered up. Unfortunately I didn't have any sets that are definitely known good. I had a couple sets that came with my SE/30 before I upgraded it, but they might be too slow for the IIci since the SE/30...
Good point. If the ROMinator doesn't even check for the complete lack of RAM, then it could well be that I'm seeing broken on-board ROMs, fundamental incompatibility with the SE/30 ROM, and RAM issues with the ROMinator. I spent some time last night trying to clean up and reflow the joints on...
Thanks for the quick response! I had posted some pics in this thread:
https://68kmla.org/bb/index.php?threads/iici-gives-sad-chimes-with-se-30-rom-silence-with-rominator-and-onboard-rom.45656/#post-505764
I do have the ROM jumper, and I've also experimented with some ROM SIMMs. I had a 256KB...
This is a great writeup, thanks!
Out of curiosity, do you happen to still have any notes as to what fixes you made led to these improvements? I'm in a similar boat right now trying to revive a battery-bombed IIci, which while nowhere as severely damaged as yours, is still stuck at the "grey...
Good eye! Thanks for the tip. I traced those out and they look OK; the outer three go to the speaker, which I know works, and I got continuity between eyelets on either end of that inner trace.
I buzzed out the VIA and iffy-looking RTC and both look OK. I also checked the UB13/UD13/UE13 logic...
Sure! Here’s how it looks right now. From where it started, I’ve so far replaced all the electrolytic caps, the 50MHz oscillator, the battery holder, the two diodes and 32.768khz crystal for the pram, and the bank A SIMM slots. One of the vias for the last Bank B slot was unfortunately just a...
Hi everyone! I've been trying to bring a IIci back to life that had pretty severe battery and cap damage. It looks like this computer had been stored vertically, but with the battery end high, so battery juice dripped downward through all of the ROMs and SIMM slots. I managed to do all the usual...