QL Issue 7 Motherboard

[RWAP]

I am testing a QL here with an issue 7 motherboard.

I am having problems with mdv1_ - I have tried 3 units and none of them will format a good (repaired) cartridge which formats fine in mdv2_

All 3 units have been very good at reading cartridges, and I have used a new roller.

The odd thing I have noticed is the extra resistors on the 8302 - I have a feeling that these are not required on the issue 7 motherboard - can anyone confirm (as the service manual only covers up to issue 6).

Anything else I could try?

[tofro]

Rich,
what exactly is the symptom of "doesn't format"? Does format and doesn't work, or returns with format failed?

You know that "Format failed" could also actually mean "write protected" - There's a bug in most ROMs that messes up the error message in this case.

Even if it sounds weird: If all else fails, I would (because most of the circuitry is shared between drives and obviously isn't broken) try replacing mdv2_ - Could easily be it doesn't correctly de-select and thus disturbs an otherwise working mdv1_.

Tobias

[Dave]

In which case just disconnecting mdv2_ would restore mdv1_ to function, wouldn't it?

[tofro]

So was the proposal, yes

[belg4rion67]

I am testing a QL here with an issue 7 motherboard.

The odd thing I have noticed is the extra resistors on the 8302 - I have a feeling that these are not required on the issue 7 motherboard - can anyone confirm (as the service manual only covers up to issue 6).

My QL has issue7 board and the extra resistor are not present!