I just now took a look at Erwin-c64's profile. He last logged in at 2014.
Per [
here], pietja is also in the Netherlands.
By changing Chips from another of my 5160 s i found out:
The Bios Chip 1501512 is faulty.
So, chip U18 of the 11/08/82 dated BIOS.
Now my question:
Do you have a chance to burn (may be an EPRON 27256) as replacement for that chip?
Or another idea how i can get it working again?
Because the 5160 was previously working, we can rule out a bent pin on the 1501512 ROM.
And because another 5160 BIOS ROM set worked, the ROM support circuitry, and the sockets, are good.
Try cleaning the pins on the 1501512 ROM. If that fails to rectify the situation, then the only fixes are:
* Substitution with a good 1501512 ROM; or
* Substitution with a suitably programmed 27C256 (or equivalent).
The code to go into a 27C256 EPROM (or equivalent) is at [
here]. The fact that the faulty ROM is 1501512, together with your "
i have an Old IBM 5160", implies that you have the early ('64-256KB') version of the IBM 5160 motherboard. Therefore, per [
here], whoever programs the EPROM needs to know not to use an NEC branded 27C256.