INT 15,C0 - Return System Configuration Parameters (PS/2 only)

AH = C0

on return:

CF = 0 if successful

= 1 if error

AH = when CF set, 80h for PC & PCjr, 86h for XT

(BIOS after 11/8/82) and AT (BIOS after 1/10/84)

ES:BX = pointer to system descriptor table in ROM of the format:

% Offset Size Description

00 word length of descriptor (8 minimum)

02 byte model byte (same as F000:FFFE, not reliable)

03 byte secondary model byte

04 byte BIOS revision level (zero based)

05 byte feature information, see below

06 dword reserved

% Feature Information

¦7¦6¦5¦4¦3¦2¦1¦0¦ Feature Byte

¦ ¦ ¦ ¦ ¦ ¦ ¦ +---- reserved

¦ ¦ ¦ ¦ ¦ ¦ +----- 0=PC bus, 1=Micro Channel

¦ ¦ ¦ ¦ ¦ +------ Extended BIOS Data Area (~EBDA~)allocated

¦ ¦ ¦ ¦ +------- wait for external event supported

¦ ¦ ¦ +-------- ~INT 15,4F~ used (kbd intercept)

¦ ¦ +--------- ~RTC~ present

¦ +---------- 2nd ~8259~ present

+----------- DMA channel 3 used by fixed disk BIOS

- see ~MACHINE ID~