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someperson
October 26th, 2013, 02:18 PM
My Tandy 1000 TX came a WD93028 XT IDE drive and 8-bit IDE controller. The original drive died, and I have installed a Seagate ST351A/X in its place. I am quite sure I have it jumpered correctly, but the drive is being detected with the wrong geometry. The correct CHS values are 820/6/17, but it is showing up as 782/4/17. Here is everything I have tried so far:

* SpinRite 5.0 -- Warned about the wrong drive geometry when opening; could not proceed into the program because it stalled during the memory test
* PC Check -- Seems worthless on this computer. Detected numerous incorrect information about the PC, including the wrong drive geometry and some extended RAM that is nonexistent
* HSECT -- Was able to low-level format the drive, but it still uses the wrong geometry. Did not prompt for CHS values

SpinRite says that I need to fix this in my BIOS, but the Tandy 1000 TX has no BIOS settings of any kind as far as I can tell. Is there anything else I can try?

leeb
October 26th, 2013, 02:44 PM
I see this problem in the XT devices I have too... I just happen to have multiples of the same drive they used... conner 2024s...

You may need to consider using a DDO to interceed for the inflexible BIOS, and possibly then be able to use much larger capacities.

:D

someperson
October 26th, 2013, 02:49 PM
I see this problem in the XT devices I have too... I just happen to have multiples of the same drive they used... conner 2024s...

You may need to consider using a DDO to interceed for the inflexible BIOS, and possibly then be able to use much larger capacities.

:D
I've used overlays on newer PCs for this same kind of thing before, but wasn't aware they existed this far back. What software would you suggest I try with this machine?

Stone
October 26th, 2013, 03:09 PM
IIRC, LLF of an IDE drive is a no-no. Something about factory-written servos that can't be done without specific equipment.

Chuck(G)
October 26th, 2013, 03:10 PM
I'm assuming that your 8-bit IDE (well, actually XTA) controller was packaged with the WD drive. The geometry's in the controller BIOS. You could patch it band burn a new PROM.

XTA is not really the same as IDE, even though people call it that. It's more like a ST506-type drive with an integrated controller. AFAIK, none of the standard IDE command extensions are used.

someperson
October 26th, 2013, 03:42 PM
I'm assuming that your 8-bit IDE (well, actually XTA) controller was packaged with the WD drive. The geometry's in the controller BIOS. You could patch it band burn a new PROM.

XTA is not really the same as IDE, even though people call it that. It's more like a ST506-type drive with an integrated controller. AFAIK, none of the standard IDE command extensions are used.
I don't have whatever I would need to read and burn a PROM, nor would I know how to patch it. What confuses me here is that the wrong geometry that is being detected results in a larger drive than the WD. How is this possible if it's using the same geometry that drive used?

modem7
October 26th, 2013, 04:54 PM
IIRC, LLF of an IDE drive is a no-no. Something about factory-written servos that can't be done without specific equipment.
A low-level format is the mechanism that is used on some IDE drives in order to switch the drive into a different translation geometry.

Chuck(G)
October 26th, 2013, 04:55 PM
In my "Hard Drive Bible", the WD93028 is listed as 782/2/27, but the 93044 is listed as 782/4/27. I ssupect that the same BIOS was used for both and that the drive choice is made 'on the fly", but that's just a guess.

What's the part number on the XTA controller?

someperson
October 26th, 2013, 05:26 PM
In my "Hard Drive Bible", the WD93028 is listed as 782/2/27, but the 93044 is listed as 782/4/27. I ssupect that the same BIOS was used for both and that the drive choice is made 'on the fly", but that's just a guess.

What's the part number on the XTA controller?
The part number is 61-000347-00.

modem7
October 26th, 2013, 05:36 PM
The part number is 61-000347-00.
If that number is on the ROM chip, then the number is probably the BIOS part number and not the card part number.

Does your card look like the one pictured in the recent thread [here (http://www.vintage-computer.com/vcforum/showthread.php?39749-Hard-Drive-Interfaces-XT-IDE-vs-AT-IDE)]?

someperson
October 26th, 2013, 05:38 PM
If that number is on the ROM chip, then the number is probably the BIOS part number and not the card part number.

Does your card look like the one pictured in the recent thread [here (http://www.vintage-computer.com/vcforum/showthread.php?39749-Hard-Drive-Interfaces-XT-IDE-vs-AT-IDE)]?
That number is from a sticker on the bottom of the card. The ROM's part number is 62-000290-060. It does look quite similar to that card.

vwestlife
October 26th, 2013, 09:43 PM
IIRC, LLF of an IDE drive is a no-no. Something about factory-written servos that can't be done without specific equipment.

The ST-351A/X (and all IDE-XT drives, for that matter) is a stepper motor drive. A low-level format won't hurt it.

Mike Chambers
October 27th, 2013, 05:01 PM
Funny. I have the exact same controller, in the exact same Tandy, with the exact same ST351A/X replacement drive. I've just been living with the smaller capacity, but if you find a solution please let me know.

fatwizard
October 29th, 2013, 03:11 AM
I have the exact same controller from a Tandy that is currently installed in a DTK Turbo XT clone. Following this thread made me curious so I pulled out my one ST 351 A/X drive and hooked it up. I discovered it running at reduced capacity just as described here. I had completely missed it when I tested the drive initially, having been overjoyed to finally acquire a working "X" drive and adapter.

This particular drive hasn't been happy tonight about being asked to operate at full capacity, and has required some massaging. However, when I used the low level format routine in the WDXT-150 adapter ROM, I was able to do a DOS 6.22 fdisk and format of the whole drive at full capacity. I booted DOS from a floppy and ran debug. The command is g=c800:5 to enter the LLF program. It then prompts for a drive letter (C: is default), interleave, which I changed to 1, then it asks if you want to dynamically configure the drive. Answer "Y" and specify 820 6 821 821 (I leave the last two entry's out as I don't have better values than the defaults) for drive parameters. When prompted to virtually configure the drive, I chose "N"

This has worked for me on the bench tonight. It's running Spinrite at this very moment. The jumpers are set 1&2, 7&8 closed.

Since I had both the controller and the drive I had to check it out, and discovered something rather glaring I had missed in the process. I hope this helps.

someperson
October 30th, 2013, 06:48 PM
I have the exact same controller from a Tandy that is currently installed in a DTK Turbo XT clone. Following this thread made me curious so I pulled out my one ST 351 A/X drive and hooked it up. I discovered it running at reduced capacity just as described here. I had completely missed it when I tested the drive initially, having been overjoyed to finally acquire a working "X" drive and adapter.

This particular drive hasn't been happy tonight about being asked to operate at full capacity, and has required some massaging. However, when I used the low level format routine in the WDXT-150 adapter ROM, I was able to do a DOS 6.22 fdisk and format of the whole drive at full capacity. I booted DOS from a floppy and ran debug. The command is g=c800:5 to enter the LLF program. It then prompts for a drive letter (C: is default), interleave, which I changed to 1, then it asks if you want to dynamically configure the drive. Answer "Y" and specify 820 6 821 821 (I leave the last two entry's out as I don't have better values than the defaults) for drive parameters. When prompted to virtually configure the drive, I chose "N"

This has worked for me on the bench tonight. It's running Spinrite at this very moment. The jumpers are set 1&2, 7&8 closed.

Since I had both the controller and the drive I had to check it out, and discovered something rather glaring I had missed in the process. I hope this helps.

Sure enough, this works! Thank you very much for figuring this out; I never would have thought that the controller would have LLF software in its ROM.