Today was a mixed bag of retro computing...
Thanks to vogons user @Balog i now have a second FastRAM Card and a 287 co-processor for my ast premium 286.
First good news:
The 287 co-processor works perfectly fine.
I removed the "jumper" co-processor and installed the new one. That was simple.
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The FastRAM card itself works. It detects the 512k ram and works.
Now the Problem:
If i install both fast ram cards only one card works. You can set the switches for first/second card and give each one an address.
Each card for itself works (mine with 1MB and the other one with 512k). But i cant get the to work together.
My theory is that the first card has to be fully populated before the second card is used. But i have not enough memory chips (missing at least 36 chips to test this theory)...
At least i know the second card works.
Now the really bad news.
I think i have killed the 5 1/4 floppy drive.
While i was tinkering with the computer i wanted to boot from a 3 1/2 floppy.
I connected the floppy drive to the system but i reversed the data cable.
I noticed the drive lights are both on and turned off the computer.
I turned around the data cable and started again.
From that moment i can not get the 5 1/4 drive to read disks.
The drive seeks normal on bootup, and when i want to read from it it starts to spin , drops the head and after 5-10 seconds i get a general reading error.
Does somebody have an idea what could be blown? here are some pictures of the drive.
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