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Xebec and ST-506

k2x4b524[

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Greetings.

I have come across a few NOS ST-506 drives, and got one to work in on of my 5160s on a WD controller. I would like to make one work in my 5150 on a Xebec controller. I've searched the forums, however my search-fu is definetly not black-belt, more like just walked into the dojo. Anyway, is it possible to make one run on the IBM Xebecs bone stock, or do i need to mod the rom? If the latter, i may just find more of the WD controllers. I've a nice 4 drive MFM coming, i might play with that...
 
I used to run an ST506 on my 5160 clone using a Xebec (type 2) controller. The trick was burning a new PROM with the geometry and, IIRC, a slower step rate. Used it for a couple of years--and still have the drive. I got the ST506 with the clone and controller. The vendor couldn't make the combo work, so the 506 was free; he charged only for the controller.
 
... mod the rom?
If taking that route:

Note that the BIOS ROM is not a 27xxx EPROM, or compatible. It is the same as what was used on the IBM 5150 motherboard.

Like with the IBM 5150 motherboard, if you want to use a 27xxx EPROM, an adapter is required. You end up with the undesirable situation shown at [here], i.e. the Xebec controller becoming quite 'wide'.

As shown at [here], adapter-less ROM solutions could be:
- 2564 EPROM (if pins 1,2,27,28, do not present a problem on the Xebec controller)
- MCM68764/MCM68766 EPROM
 
My Xebec was non-IBM branded.
1.jpg
A 104866, since it was purchased from a clone vendor.
 
Sure, if you want to write your own (loadable) driver.

That question was asked on Stack Exchange Retrocomputing once actually. Since the drive tables are re-vectorable by software it seems "simple enough" to do at some point after INT 19H:


Are you aware of any products sold "back in the day" or any recent projects that do that?
 
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