[Coco] CoCo Model 1 Cartridge Port

[Rick Ulland]

On 12/24/21 8:48 AM, Charles Hudson wrote:
> Following your advice I moved the cable to the last connector (on the 
> end with two connectors) and repeated the process of "dksini0".  This 
> time the drive light came on and I could hear the stepper motor move 
> the head.  I failed to count the steps - I was completely surprised - 
> but a dozen steps or more activity ceased and the light went out.  The 
> result on the screen once again stated IO ERROR.
>
> I then tried repeating the disk format.  This time I heard the 
> mechanism straining; no regular repeated stepping and after a few 
> steps with long pauses between them the activity ceased and I got 
> another IO ERROR message.
>
I'd bet dollars to donuts Art is correct. The way a CoCo drive is 
supposed to work, you turn it own. The head position is unknown. First 
operation steps the head a whole buncha times, to make sure it's banged 
against the end stop for a while. DECB still doesn't know the head 
position, but assumes surely this is 0 and counts from here until death. 
If the head doesn't move, or doesn't move properly, DECB doesn't know 
and forges ahead until there is a read error.

Pop the top, watch the show. Bring hair clipper oil for the dry slide 
rails. And Merry Christmas.

-ricku