Original PC Hardware Reference

CD: 8 Original PC Hardware Reference
Table 2 IBM Family/1 (PC, XT, AT) System BIOS Dates
ID, BIOS
Submodel, Drive
System CPU Speed BIOS Date Revision Types
PC 8088 4.77MHz 04/24/81 FF — — —
PC 8088 4.77MHz 10/19/81 FF — — —
PC 8088 4.77MHz 10/27/82 FF — — —
PCjr 8088 4.77MHz 06/01/83 FD — — —
PC-XT, PPC 8088 4.77MHz 11/08/82 FE — — —
PC-XT 8088 4.77MHz 01/10/86 FB 00 01 —
PC-XT 8088 4.77MHz 05/09/86 FB 00 02 —
PC Convertible 80C88 4.77MHz 09/13/85 F9 00 00 —
PC-AT 286 6MHz 01/10/84 FC — — 15
PC-AT 286 6MHz 06/10/85 FC 00 01 23
PC-AT 286 8MHz 11/15/85 FC 01 00 23
PC-XT 286 286 6MHz 04/21/86 FC 02 00 24
The ID, submodel, and revision byte numbers are in hexadecimal.
— means this feature is not supported.
The BIOS date is stored in all PC-compatible systems at memory address FFFF5h. To display the
date of your BIOS, a simple DEBUG command can be used to view this address. DEBUG is a command
program supplied with MS-DOS. At the DOS prompt, execute the following commands to
run DEBUG, display the date stored in your BIOS, and then exit back to DOS:
C:\>DEBUG
-D FFFF:5 L 8
FFFF:0000 30 31 2F-32 32 2F 39 37 01/22/97
-Q
In this example, the system queried shows a BIOS date of 01/22/97.
PC Technical Specifications
Technical information for the personal computer system and keyboard is described in this section.
Here, you find information about the system architecture, memory configurations and
capacities, standard system features, disk storage, expansion slots, keyboard specifications, and
physical and environmental specifications. This kind of information might be useful in determining
what parts you need when you are upgrading or repairing these systems. Figure 3 shows the
layout and components on the PC motherboard.