Re: Two 1541-II drives with problems

On 04/19/2014 02:14 PM, Ville Laustela wrote:
>
> Hello!
>
> I found out that I own two Commodore 1541-II disk drives, both in a non-working state.
>
> Testing with a measured-good PSU, I got the following results with both drives:
>
> - power on: normal activity (power led on, spindle runs and drive led lights for few seconds, then stop)
> - connected to a C64: drive resets with the computer normally
> - attempting to load halts at "SEARCHING FOR": drive spins (with leds on) but the stepper doesn't move. Only way out is to reset the computer.

Last month a friend and I fixed an SX-64 where the drive was behaving 
that way. It reset properly, you could read the error channel but as 
soon as you tried to actually load something from a disk it hung.

In our case the problem was... the 6502. Once we replaced the CPU 
everything worked, put the old CPU back in and the problem was back. We 
never explored it in detail, but wondered whether the SO-pin on the 6502 
the 1541 uses to tell the CPU that a Byte is ready stopped working. He 
kept the CPU since there are other systems were it might still be useful 
for.

So if the CPU is in socket, try a different one.

  Gerrit



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