More Commodore PET drives - more help?

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Fri Sep 24 19:10:55 2004

> 1) Commodore SFD-1001
> This is the IEEE-488 (PET) single-drive that looks
> very much like a VIC/C64 1541 serial drive.
>
> The drive powers on, and both the POWER and drive LED
> come on solid RED and stay that way - no other activity
> is observed - it doesn't matter if the IEEE bus is
> connected or not, and resetting the IEEE bus (via PET
> power-on) has no effect. If the PET tries to access the
> IEEE bus, it hangs, presumably waiting for an acknowlege
> that never comes (?)
>
> It looks like the on-board CPU is not running at all.

I would guess that's likely to be the case (although I've never worked on
this unit).

In which case I'd start by checking the +5V power rail, then check the
CPU clock and reset pins (make sure the thing isn't held in the reset
state), then see what the aaddres and data lines are doing.

-tony
Received on Fri Sep 24 2004 - 19:10:55 BST