INT 15H c0H: Get System Parameters
Expects: AH c0H
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Returns: AH 00H (and CF=NC=0) successful, and ES:BX points to valid data
86H (and/or CF=CY=1) unsuccessful
ES:BX addr of system configuration table
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Info: This returns a pointer to a table that describes the system.
BiosSysParmsRec
Offset Size Contents
▀▀▀▀▀▀ ▀▀▀▀ ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
+0 2 wLen length of this table, in bytes
+2 1 yModel PC=ff,XT=fe or fb, PCjr=fd, AT=fc, unknown=ff
+3 1 ySubModel PC,XT,PCjr,AT=00; AT=01, XT-286=02
+4 1 yRevLvl BIOS revision level (0=initial release)
+5 1 rFeatures1 features bits:
┌7┬6┬5┬4┬3┬2┬1┬0┐
│ │ │ │ │ │ │ │0│
└╥┴╥┴╥┴╥┴╥┴╥┴╥┴-┘ bit mask
║ ║ ║ ║ ║ ║ ║ ╚══► 0: 01H (reserved)
║ ║ ║ ║ ║ ║ ╚════► 1: 02H 0=PC-type I/O channel
║ ║ ║ ║ ║ ╚══════► 2: 04H 1=Extended BIOS area allocated
║ ║ ║ ║ ╚════════► 3: 08H 1=wait for ext event supported
║ ║ ║ ╚══════════► 4: 10H 1=INT 15H 4fH supported by INT 09H
║ ║ ╚════════════► 5: 20H 1=real-time clock is present
║ ╚══════════════► 6: 40H second interrupt chip is present
╚════════════════► 7: 80H hard disk BIOS uses DMA chnl 3
+6 1 rFeatures2 (reserved)
+7 1 rFeatures3 (reserved)
+8 1 rFeatures4 (reserved)
+9 1 rFeatures5 (reserved)
10 size of this structure
See Also: INT 15H (extended AT services)
BIOS Data Area
ROM-BIOS Functions
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