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leaknoil
November 15th, 2008, 01:20 PM
I have a dead IIc+ I would like to get running. On the off chance someone here may have seen symptoms similar to this I'm posting a couple shots of the screen. The first one shows up when powered on. The second one will show up after resetting the box a few times.

Does the same thing regardless if the keyboard and floppy drive is connected or not.

I've tried reseating all the socketed IC's in there but, no change. As rare as the IIc+ seems to be I may not be able to find parts anyway if its anything custom.

Any thoughts ?

tezza
November 15th, 2008, 02:06 PM
I saw screens like this a lot when I was repairing my Apple IIs. Sometimes it was RAM, sometimes it was one of the logic chip.

At least you are getting video, so that circuitry is probably ok.

Tez

leaknoil
November 15th, 2008, 02:55 PM
I just found a corroded and broken resistor R57. Going to replace it and see what happens. Wish I could find IIc+ schematics to see what it connects to. I'm not sure if it corroded and broke off or blew up. Its too messy to tell but, if it was voltage maybe whatever is downstream of it took a hit too.


edit: OK that didn't fix anything but, it needed to be replaced anyway. Never had a single resistor take down a computer before anyway.

Druid6900
November 15th, 2008, 07:08 PM
What's the major difference between the IIc and the IIc+?

channelmaniac
November 15th, 2008, 08:07 PM
What do you get when you power it up with the keyboard disconnected? (That forces it into built-in diagnostics)

It's been so long since i've worked on a //c+ that I don't remember all the issues I've seen on them... Hell, it's been since the mid 90s.

Since it appears to not be doing anything, I'd start with checking the monitor ROM and the CPU.

magnusfalkirk
November 15th, 2008, 09:23 PM
What's the major difference between the IIc and the IIc+?

The major differences between the IIc and the IIc+ are built in 4MHz Zip Chip and built in 3.5 drive in the IIc+. There may be others but those are the two biggest differences I know of off the top of my head.

Dean

Yzzerdd
November 16th, 2008, 05:27 AM
What's the major difference between the IIc and the IIc+?

Difference is I own one but not the other.

hehe, I had to.

--Jack

Terry Yager
November 16th, 2008, 09:41 AM
The major differences between the IIc and the IIc+ are built in 4MHz Zip Chip and built in 3.5 drive in the IIc+. There may be others but those are the two biggest differences I know of off the top of my head.

Dean

Also, the keyboards are different, as I discovered once when trying to resurrect a //c+ with parts from a //c. Not just the key layout, the keyswitches themselves are not swappable. Of course, with the different key layout, the plastics do not interchange either. (just a heads-up, in case you're tempted to grab a //c for parts).

--T

leaknoil
November 16th, 2008, 10:48 AM
What do you get when you power it up with the keyboard disconnected? (That forces it into built-in diagnostics)

It's been so long since i've worked on a //c+ that I don't remember all the issues I've seen on them... Hell, it's been since the mid 90s.

Since it appears to not be doing anything, I'd start with checking the monitor ROM and the CPU.


It goes to that first screen without the keyboard attached as well. Just have no keys to press to get to the second screen.

leaknoil
November 16th, 2008, 10:51 AM
Also, the keyboards are different, as I discovered once when trying to resurrect a //c+ with parts from a //c. Not just the key layout, the keyswitches themselves are not swappable. Of course, with the different key layout, the plastics do not interchange either. (just a heads-up, in case you're tempted to grab a //c for parts).

--T

I have a IIc here I disassembled to see if there were any parts I could swap and there really aren't. Pretty much everything is unique to one or the other. Of course the few parts that are them same are soldered to the motherboard on one or the other.

Druid6900
November 16th, 2008, 12:01 PM
Ok, if the motherboard is, basically, the same, then searching on "Apple IIc plus manual" (minus the quotes, of course), will bring up several instances of the IIc technical Reference Manual.

leaknoil
November 16th, 2008, 02:37 PM
Ok, if the motherboard is, basically, the same, then searching on "Apple IIc plus manual" (minus the quotes, of course), will bring up several instances of the IIc technical Reference Manual.

Totally different

Terry Yager
November 16th, 2008, 06:17 PM
Pretty much my experience too...

--T

Druid6900
November 16th, 2008, 06:43 PM
Totally different

Well, when I asked what the major differences between to IIc and the IIc+, I guess someone should have said "totally different motherboard", right?

Terry Yager
November 16th, 2008, 07:58 PM
Well, when I asked what the major differences between to IIc and the IIc+, I guess someone should have said "totally different motherboard", right?

Uhh, totally different mainboard, dude...totally different everything, in fact...

(Of course, they may be electronically identical, schematic-wise, just physically different...)...

--T