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RuudB
May 28th, 2014, 04:57 AM
Hallo allemaal,

I was a bit scrolling through the Technical Reference for the IBM 5155 and the 5160 and suddenly saw on page 5-23 that this XT BIOS supports the 720 KB and 1.2 M drives. I never ever heard of that! AFAIK a 720 KB drive can be supported by setting some parameters in config.sys, DRIVEPARM IIRC. But for using a 1.2 MB drive you cannot use the standard FDC; you'll need an AT type.

Has anybody more info on this item? TIA!

fs5500
May 28th, 2014, 05:38 AM
Hallo allemaal,

I was a bit scrolling through the Technical Reference for the IBM 5155 and the 5160 and suddenly saw on page 5-23 that this XT BIOS supports the 720 KB and 1.2 M drives. I never ever heard of that! AFAIK a 720 KB drive can be supported by setting some parameters in config.sys, DRIVEPARM IIRC. But for using a 1.2 MB drive you cannot use the standard FDC; you'll need an AT type.

Has anybody more info on this item? TIA!

720KB Drive supports on IBM PC/PC XT all bios.
I've tested Solo Flight (3.5" 720KB) on IBM PC XT (11/08/82) with 256KB RAM.
But to access DOS system or files, you need to boot IBM/MS DOS 3.2 or higher.
1.2MB Drive supports on IBM PC XT (01/10/86) or later, but you needs FDC controller to supprt 1.2MB with XT compatible.
I think it is Not so stable to access 1.2MB/1.4MB FDD on XT Compatible.