Disk Drive select settings

[atrax27407]

Anyone have a list of jumper settings for drive select - Schmitzi?

[+arcadeshopper]

for what drive..they are all unique some are similar but not exactly the same

[atrax27407]

As I understand it, if the jumpers are:

 

DS0 = DSK1

DS1 = DSK2

DS2 = DSK3

 

etc.

 

If they are designated:

 

DS1 = DSK1

DS2 = DSK2

DS3 = DSK3

 

etc.

 

There are variants of the designation but I assume that the pattern holds true.

[+arcadeshopper]

yes that's correct

[+Schmitzi]

I have manuals for many drives, but the pattern above is correct

[apersson850]

This assumes you have all drives connected in parallel via the ribbon cable.

Some cables will shift the drive select signal, in which case all drives are set as being DSK1. The wire shift in the cable will route select for DSK2 to the DSK1 input on the second drive in such a case.

[+arcadeshopper]

This assumes you have all drives connected in parallel via the ribbon cable.

Some cables will shift the drive select signal, in which case all drives are set as being DSK1. The wire shift in the cable will route select for DSK2 to the DSK1 input on the second drive in such a case.

 

DRIVE TWIST CABLES DO NOT WORK RIGHT ON THE TI-99/4A DON'T USE THEM

 

Seriously, don't!

Greg

 

PS: I have brand new fancy straight through cables on arcadeshopper.com if you need some

[apersson850]

Oh yes they do, if they are done correctly. That's what TI supplied from start, but they used a small printed circuit board to do the twisting. The principle was the same, though.

Personally, I don't see the point, though, as it's so easy to program the drives, and then you can have straight cables. But I happen to be a professional in the electric field. People wary of touching electroncis may see it differently.

Edited August 16, 2018 by apersson850

[+OLD CS1]

Oh yes they do, if they are done correctly. That's what TI supplied from start, but they used a small printed circuit board to do the twisting. The principle was the same, though.

Personally, I don't see the point, though, as it's so easy to program the drives, and then you can have straight cables. But I happen to be a professional in the electric field. People wary of touching electroncis may see it differently.

 

The standard PC interface adopted by IBM and the Shugart interface are different -- the former has two motor control lines and two drive select lines, while the latter has one motor control line and four drive select lines. This is why most PC twist cables will not work with the TI, and what those TI circuit boards did was to move the drive selects one over.

 

IBM had reasons for going with a twisted cable. First, because it wanted a drop-in-place solution for additional drives, which moving jumpers would not provide but a twisted cable would. It was also easier to manufacture drives without DS or SEL jumpers on-board, which you will find with a good number of 3.5" drives, in particular.

 

I follow Electroboom methods of pixie wrangling and things work out just fine for me.

[+arcadeshopper]

Oh yes they do, if they are done correctly. That's what TI supplied from start, but they used a small printed circuit board to do the twisting. The principle was the same, though.

Personally, I don't see the point, though, as it's so easy to program the drives, and then you can have straight cables. But I happen to be a professional in the electric field. People wary of touching electroncis may see it differently.

 

PC DRIVE TWIST CABLES AREN'T DONE CORRECTLY