INT 15h, C0h (192) Return System Configuration many
Reports the machine model number, sub-model number, BIOS revision
level, and other hardware-specific attributes.
On entry: AH C0h
Returns: Carry Set if error, else cleared
AH 0
ES:BX Pointer to a System Descriptor Table
--------------------------------------------------------------------------
Notes: This service is not available for the PC, PCjr, XT
dated 11/08/82, and the AT dated 1/10/84. Use the
return state of AH to determine if the service is
returning valid information.
System Descriptor Table
Description Length (byte) Value
Table length 1 8
System model number 1 ?
Sub-model number 1 ?
Bios Revision level 1 ?
Feature Information 1 ?
Reserved 4 0
Feature Information
7 6 5 4 3 2 1 0
x . . . . . . . Fixed Disk BIOS uses DMA channel 3
. x . . . . . . 2nd interrupt chip present
. . x . . . . . Real-time clock present
. . . x . . . . Keyboard intercept called in INT 09h
. . . . x . . . Wait for external event supported
. . . . . x . . Reserved
. . . . . . x . Reserved
. . . . . . . x Reserved
Notes: The XT dated 1/10/86 has a bug in its Feature
Information. It incorrectly states that the second
interrupt chip is present (bit 6 is set) and that
the fixed disk BIOS doesn't use DMA channel 3 (bit 7
is clear). Both of these are incorrect. To test for
this condition, if the model number is FBh and the
BIOS level is 1, then ASSUME that the Fixed disk
BIOS does use DMA channel 3 and the second interrupt
chip is not present.
Programs using the DMA channel 3 presence must also
be aware that other adapters may be using this
channel, such as the IBM Network Adapter, which will
not be reflected in the Feature Information byte.
See INT 15h, Service 4Fh, for more information on
Keyboard intercept (bit 4 of the Feature Information
byte) and see INT 09h for more information of the
hardware keyboard interrupt.
See INT 15h, Service 41h, for more information on
the Wait for External Event (bit 3 of the Feature
Information byte).
Seealso:
This page last updated on Fri Nov 30 10:49:50 MSK 2001
Copyright © 1992-2001, Vitaly Filatov, Moscow, Russia
Webmaster