rfutscher@pbs.org (10/04/90)
In article <3343@amc-gw.amc.com>, jwbirdsa@amc-gw.amc.com (James Birdsall) writes: > I just ran into an interesting problem with an RLL drive. > > I have a Toshiba MK134 and a Western Digital RLL controller (8-bit, I > forgot to look at the model the last time I had the computer open). The > Toshiba is ~65M and has 7 heads. When the RLL 26 sectors/track are remapped > to 17 sectors/track, the number of cylinders is still under the BIOS limit > of 1024. > I just tried to install a Mitsubishi MR535. It is the same size but only > has 5 heads, so the number of remapped cylinders is well over 1024, making > about 22M inaccessible. > I tried Disk Manager (came with the drive) as a last ditch; it tried to > tell the controller BIOS to not remap the drive, but returned with the > message "THE CONTROLLER BIOS DOES NOT SUPPORT NONSTANDARD CONFIGURATIONS." > > So, even through I'm running the drive RLL, I'm only getting ~44M (which > is the MFM rating!). And Disk Manager (which I don't want to run but I want > the extra space more) can't help with my present controller. > > So, can somebody point me at an 8-bit RLL controller that CAN handle > nonstandard configurations? I had the same problem when I installed my 60 meg drive. I found the following solutions: 1) Use disk manager or another program. When I tried this I kept haveing problems with programs, ie disk utilities. Booting from floppies is a pain because disk manager has to be on all your bootable floppies. 2) Buy a newer BIOS that supports your drive/controler combination. My hardware is a little different and I did not think I could find a updated, compatable BIOS. 3) There are shareware programs to change your BIOS. Of course you have to be able to reprogram EPROMs. 4) Buy a BIOS extention. I had unused EPROM sockets on my mother board so I tried this solution. I have been very happy with the results. My RLL controler and hard disk is now suported by my BIOS. I did have to give up some memory locations between 640k and 1 meg. If you want the name of the company that made my BIOS extention let me know. rfutscher@pbs.org