Just got a 5160 (BIOS 82) and...

[usotsuki]

Right now I have yet to bootstrap it. HD that came with it didn't work and I don't know about the FDD (which I've pulled since I'm planning to replace it with a 3.5" drive as soon as I have a bracket).

I am considering in the reasonably near future buying or having made something like an XTIDE - until then I'll just have to hope I can boot off either a padded 1.44 or a padded 720... (ETA: I don't know how well this will work which is kind-of my concern, though supposedly it's supposed to work with DR DOS 7.03 or something...)

This is the oldest vintage computer I've owned - prior it was the Tandy 1000 SX, and I also have a working Apple //e which is currently decommissioned. Bit n00b here but been talking a bit with other XT enthusiasts. xD

 

[modem7]

Just got a 5160 (BIOS 82)

So 5160 motherboard containing 11/08/82 BIOS.

Right now I have yet to bootstrap it. HD that came with it didn't work and I don't know about the FDD (which I've pulled since I'm planning to replace it with a 3.5" drive as soon as I have a bracket).
I am considering in the reasonably near future buying or having made something like an XTIDE - until then I'll just have to hope I can boot off either a padded 1.44 or a padded 720... (ETA: I don't know how well this will work which is kind-of my concern, though supposedly it's supposed to work with DR DOS 7.03 or something...)

Conicidentally, I have my IBM 5155 open presently, and it uses the same motherboard/BIOS (5160 motherboard containing 11/08/82 BIOS).

With the original IBM floppy controller remaining in place, if I substitute the 360K drive with a 1.44M drive, I cannot boot from a 1.44M boot diskette, but I can boot from a 720K diskette (IBM-DOS 3.3).

 

[usotsuki]

Yeah, I've got a 16-bit multi-i/o card hooked up. Supposedly these things work in an XT apart from the IDE part. Got a 16-bit VGA card in here that works and an Intel EtherExpress 8/16 I can't test yet. Keyboard was stock, though a bit beat up.

 

[Mike Chambers]

So 5160 motherboard containing 11/08/82 BIOS.


Conicidentally, I have my IBM 5155 open presently, and it uses the same motherboard/BIOS (5160 motherboard containing 11/08/82 BIOS).

With the original IBM floppy controller remaining in place, if I substitute the 360K drive with a 1.44M drive, I cannot boot from a 1.44M boot diskette, but I can boot from a 720K diskette (IBM-DOS 3.3).

both you and usotsuki can boot them from a 1.44 MB DR-DOS 7.03 disk. it WILL work.

 

[modem7]

Yeah, I've got a 16-bit multi-i/o card hooked up.

If that 16-bit multi-IO card contains a floppy controller, then it is sure to support a 500 Kbps data transfer rate (required for 1.44MB operation), however the 11/08/82 BIOS does not have 1.44MB support.

The third revision BIOS for the 5160 motherboard contains 1.44MB support, however puting that BIOS in a first revision motherboard may not be valid. That's because the first revision motherboard has 4 banks of 64K RAM, whereas the third revision motherboard has 2 banks of 64K RAM and 2 banks of 256K RAM. The third revision BIOS might get confused if it expects 2 banks of 64K RAM and 2 banks of 256K RAM, but physically there are 4 banks of 64K RAM. But maybe somone on these forums has tried that, and it works.

An option is to disable the floppy controller part of the multi-IO card, and fit something like the 'intelligent' floppy controller shown at http://members.dodo.com.au/~slappanel555/transfer/35_inch_drive.htm

 

[modem7]

both you and usotsuki can boot them from a 1.44 MB DR-DOS 7.03 disk. it WILL work.

Even though my original IBM controller doesn't support a 500 Kbps data transfer rate?

 

[usotsuki]

And even though INT13h on such a BIOS doesn't know 18-sector formats?

 

[mbbrutman]

Nothing is going to make a high density drive work at the higher data rate on an older controller that doesn't have the higher data rate. However, DOS can supply it's own parameter table for floppy drives, so the lack of BIOS support for a drive other than a 360KB drive is not an issue.

(DRIVPARM and DRIVER.SYS can be used to do this. And the later DOSes figure out what kind of drives you have even on older machines because the BIOS has no way to tell DOS what is hooked up.)