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Got a hold of a cheap IIci and made the logic board sparkle again. Lifted dull-looking chips, cleaned the legs and pads, drag-soldered back fresh. Nice new caps, no broken traces in the acid zones, power circuit works. However, either the ROMSEL circuit or the ROM chips themselves are again bad, like in my IIcx, though the machine works great with a slot ROM. Am I cursed to irradiate every mask ROM I touch?!
M
max1zzz
Those mask ROM's are starting to go bad very quickly these days, I have had quite a few myself. Luckily at least for stuff like the IIcx and IIci they use chips with a standard pinout and are pretty easy to replace
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Boctor
Boctor
I never thought I'd see the day, although I read somewhere that latent manufacturing problems in these can crop up after a couple decades. Unsure how true this is. I'll have to learn new desoldering techniques, or see if I can get to VCF some day and consult an expert, as it's hard to get some of those DIPs out and I don't want to ruin my boards. Good thing there's always the SIMM slot!
I'd seen mentions of cursors flickering on some Macs because of time/RTC related problems. After taking a closer look at the RTC circuitry in my cheap Mac IIcx, sure enough, it's not the video card! After scraping, tinning, and meticulous bodging, it's all right.

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Boctor
Boctor
Thanks! The Xenforo search and the high-quality threads on this site are an amazing combo. Learning about the clock/PRAM circuit from the forums also alerted me to a broken trace and possible hidden corrosion on my IIsi, which I never would've otherwise caught.
Iesca
Iesca
Were you also experiencing issues with clock drift, in addition to the cursor symptoms?
Boctor
Boctor
Not sure if I'd call it drift, but on the IIcx, a second took a very long time to elapse. Apple Personal Diagnostics won't specify why the Logic Board Components test fails, but it'll actually fail when the 1hz on the clock doesn't tick as expected, whereas Snooper and MacTest Pro don't even test it.
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I hate flea markets, unlike my children and their mother. But this morning I was well advised to go with them.
I found this nice PowerBook 180c for 30€. Even if it's dead, it would still be a bargain.
As long as we're in the mood of trying to save '040s, do you think this one is salvageable?

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Renegade
Renegade
Comes from a battery-bombed Quadra 610.
I was thinking that by cutting off all the pins and hoping that the rust could be removed, the chip could be modded into some kind of BGA-ish that could be placed on a custom adapter PCB which would fit into a 68040 socket.
A lot of effort for a less than guaranteed result, eh?
croissantking
This shutdown dialog under System 7.1 is particular to the 840AV. Normally, nothing happens when you press the power key under 7.1. It’s a customisation built into this machine’s system enabler.

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Renegade
Renegade
it seems to me that many enablers implement this functionality under 7.1
croissantking
croissantking
It is an ugly dialog box for sure! Probably made by an engineer not a designer. Still, interesting to see the progression towards the 7.5+ shutdown box we all know and love
I’m hoping to save this 040 chip, soldered to one of @zigzagjoe’s QFP2PGA boards. I ground two corners with a Dremel to be able to attach repair wires to the missing pins, which were lost to corrosion. Might give you some ideas for yours @jmacz

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jmacz
jmacz
Nice, haven’t played with the chips yet but will try to save that one with the broken pin.
Joopmac
Joopmac
cool, what about this adapter? is this an accelerator or just adapter? looks sweet.. is there a topic?
croissantking
croissantking
@Joopmac its an adapter that lets you use a quad flat pack 040 in a PGA socket, designed by @zigzagjoe. It’s freely available on his GitHub :)
Good old Bryce
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LaPorta
LaPorta
I have had the program for years. I think I’ve got Bryce 2-4 on my machines, and I also have a version for OS X as well that does run on 10.6, 10.7, etc. so much fun as a kid.
J
joshc
I spent many hours of my childhood using Bryce 2 on a Performa 6200. The rendering times were horrendous but it was worth the wait to see your render by the end of it.
Snial
Snial
@joshc , but isn't @SophieRose using a 68040 Mac to do this? So, the rendering times must be even slower? Unless it's the world's only souped-up 8 core, liquid Nitrogen cooled, 200MHz, 68060 Mac (with hacked '060 Mac OS, obvs).
My SE/30s are very ill. Stock PSU issues, mostly. They’re recapped, but their +5V rails are too low. I might try tweaking the voltage pot - but +12V is already quite high.
croissantking
croissantking
As I recall, anecdotally, they got worse after recapping. The big cap is a slightly different capacitance than the original, I hope that didn’t mess things up.
robin-fo
robin-fo
I didn‘t change the big cap..
croissantking
croissantking
Have you played with the pot yet? I’ve been putting it off as it’s a fiddle to do, but I need to try.
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