ylee@iuvax.cs.indiana.edu (Yao Chung Lee) (01/27/91)
Hi !
We got an old IBM AT (6 mhz) that does not support 1.44 3.5
inch drives. It has a DTC 5287 RLL controller.
My question is twofold, to to get into the DTC ROM menu,
we need to use debug, can someone provide the starting address
of the DTC card to do low level format as we lost the documentation
for it.
Secondly, is there any drivers out there that will let
the AT support the 3.5 inch and it does not recongize a 3.5
inch in setup.
Thank you.
Raymond Lee
Bitnet : ylee@iugold.bitnet
Internet: ylee@cs.indiana.edu
UUCP: {ames,rutgers,att}!iuvax!yleewilker@gauss.math.purdue.edu (Clarence Wilkerson) (01/27/91)
I don't know anything about the DTC 5287. In general on an AT, the Hard DISK and Floppy disk routines are in the AT bios itself, no on the disk controller board. If this is the case for the DTC, then there is no address to go to for low level boards. That's a feature found on XT type controller boards. If there is a ROM bios on board it's to allow sector translation from RLL's 26 sectors/track to the MFM 17 sectors/track. My WD controllers do this with a jumper on the board. That's also an issue for doing the formatting of the hard drive, since none of the std. AT drive type have 26 sectors/track. If there is a ROM with useful routines, I'd look around C800:000X, where X varies from one manufact. to another. For WD it's 5. Clarence Wilkerson
schuster@panix.uucp (Michael Schuster) (01/27/91)
In article <1991Jan26.163545.27685@news.cs.indiana.edu> ylee@iuvax.cs.indiana.edu (Yao Chung Lee) writes: > We got an old IBM AT (6 mhz) that does not support 1.44 3.5 >inch drives. It has a DTC 5287 RLL controller. > My question is twofold, to to get into the DTC ROM menu, >we need to use debug, can someone provide the starting address >of the DTC card to do low level format as we lost the documentation >for it. > Try g=c800:5 or g=ca00:5 > Secondly, is there any drivers out there that will let >the AT support the 3.5 inch and it does not recongize a 3.5 >inch in setup. Too bad you don't have the 339 (8 mHz); its BIOS =did= support 1.44's although the setup program didn't. If you used a modern setup program and >DOS 3.3 it would work properly. There are two choices: replace the BIOS or add to it with a set of option ROMS at $E000. Microlink (800-767-5465) sells a Phoenix BIOS for the IBM AT which provides 1.44 MB drive support. -- l\ /l ' _ Mike Schuster ...!cmcl2!panix!schuster l \/ l l l/ (_ NY Public Access CIS:70346,1745 l l l l\ (_ UNIX Systems MCI Mail,GEnie:MSCHUSTER