[Coco] Jumper settings needed

[LinuxRules]

Tony wrote:
>
>
> I have  a Revision L and Revision U M4853 in front of me.
> I KNOW I used my Rev U in a PC, as it still has a diskette inside 
> labelled "MS-DOS."
>
> On the jumper set near the FDC connector, DS1 is jumpered, and HM is 
> jumpered.
> Going rear (nearest connector) to front (towards front of drive) using 
> binary:
> 01000010  1 being jumpered.
>
> Mine also happens to have the term jumpers inserted, whic is about 1 
> inch away from edge,
> about 2 inches in from the FDC connector.
>
> Rev U and Rev L are VASTLY different on other jumpers, ie, not the 
> jumper header where DS is
> selected.
>
> Tony
>
I appreciate all the help Tony!

Checking my drive, it's a Rev C. Early one, I guess.
It has 7 positions, not 8, for the option block near the connector.
The good news is that there is one labeled HM, so I set the jumpers
to HM - was DS - and DS1 - where it already was.
The bad news is that produced no change. Arrggg.!
Well, actually, it did make one change - the head started pounding
up & down a dozen or so times as the PC tried to identify the
drive. But, no change in the "Not Ready" problem.

I also used your suggestion of setting BIOS to 720K, but
that also produced no improvement.

Guess I gonna have to order the manual(s) from "herb's stuff"
web site. Unfortunately that seems to be a slow process as
you have to Xchng email with him to select the right manual
and get a quote, then send snailmail with a check and he mails
the manuals. Most likely has to wait for check clearing also.

Ah well, if you gotta, you gotta........

As a side note, my search for M4853 returned dozens of replys
(no jumper data) and about 2 dozen claimed that it is a 360K
drive. One claimed 400K (vote for 360!). One claimed 0.72Mb.
One claimed 80trk, 720Kb. And one claimed 96tpi, 720Kb.
Dern, now I don't know for sure ?WHAT? I have...
Possibly the difference between M4853 and M4853-1 could
perhaps be the track density....48tpi vs 96tpi??

Confusion reigns.

cheers & thanks again,
johnd