[Coco] DW4 problems

[Bob Devries]

Continuing the DW4 saga....

Moving to version 4.3.0 seemed at first to have at least lessened the 
problem; I did a DSAVE last night, with very few ERROR 245's.
On Aaron's suggestion, I removed the FIFO buffer in the driver for my ATEN 
(Prolific) USB dongle. That seemed to work wonders last night, but this 
morning, it's back to square one.
I can do a MEGAREAD </X2, and get no errors. The speed result was 2:02, 
where my H0 (Quantum SCSI using SCSISYS V2) gets 0:16 !!
The IDENT for the DW modules is as follows:

4 $E1 $02AF3D . rbdw
22 $21 $8435E1 . dwio
2 $E1 $F66B73 . scdwv
1 $E1 $41B964 . scdwp

I'm unsure which CLOCK2 module this is:

2 $21 $D173CB . Clock2

Can anyone tell me? I'm concerned that timing differences between the NTSC 
and PAL models may be causing this or at least worsening it, and I wonder if 
the CLOCK2 module could be part of the problem.

The PAL Coco3's main crystal is 28.475MHz. I don't know what the E and Q 
clock lines run at; but the technical manual *may* tell me that.

@Aaron:
Is there some sort of test programme we can cobble together to try to chase 
this problem down?

I have not yet shortened my coco3 DW cable, but based on Gene's comments, it 
may not help.

Comments?

Regards, Bob Devries
Dalby, QLD, Australia