Format of Extended BIOS Data Area (PhoenixBIOS 4.0) (Cont.)
power-on self-test when the machine is reset
See Also: INT 19,MEM F000h:FFF0h
(Table M021)
Values for POST reset flag:
0000h cold boot
0064h Burn-in mode
1234h to bypass memory test (warm boot)
4321h [PS/2 except Mod 25,30] to preserve memory
5678h [Conv] system suspended
9ABCh [Conv] manufacturing test mode
ABCDh [Conv] POST loop mode
--------B-M00400074--------------------------
MEM 0040h:0074h - FIXED DISK LAST OPERATION STATUS (except ESDI drives)
Size: BYTE
See Also: INT 13/AH=01h,INT 13h/AH=0Ah,MEM 0040h:0041h
(Table M022)
Values for fixed disk last operation status:
00h no error
01h invalid function request
02h address mark not found
03h write protect error
04h sector not found
05h reset failed
06h diskette removed
07h drive parameter activity failed
08h DMA overrun
09h DMA data boundary error
0Ah bad sector flag detected
0Bh bad track detected
0Ch requested diskette media type not found
(PS/2 or extended BIOS only) unsupported track
0Dh invalid number of sectors for Format
0Eh control data address mark detected
0Fh DMA arbitration level out of range
10h uncorrectable ECC or CRC error
11h ECC corrected data error
20h general controller failed
40h seek failed
80h time out
AAh drive not ready
B0h volume not locked in drive (INT 13 extensions)
B1h volume locked in drive (INT 13 extensions)
B2h volume not removable (INT 13 extensions)
B3h volume in use (INT 13 extensions)
B4h lock count exceeded (INT 13 extensions)
B5h valid eject request failed (INT 13 extensions)
BBh undefined error
CCh write fault on selected drive
E0h status error/error register is zero
FFh sense failed
See Also: #0166
--------d-M00400074--------------------------
MEM 0040h:0074h - WD1002-27X SuperBIOS - TOTAL DRIVES, FIRST CONTROLLER ONLY
Size: BYTE
See Also: MEM 0040h:0075h"SuperBIOS",MEM 0040h:0076h"SuperBIOS"
--------B-M00400075--------------------------
MEM 0040h:0075h - FIXED DISK - NUMBER OF FIXED DISK DRIVES
Size: BYTE
See Also: MEM 0040h:0076h"FIXED DISK",MEM 0040h:0077h"FIXED DISK"
--------d-M00400075--------------------------
MEM 0040h:0075h - WD1002-27X SuperBIOS - TOTAL FIXED DRIVES, BOTH CONTROLLERS
Size: BYTE
See Also: MEM 0040h:0074h"SuperBIOS",MEM 0040h:0076h"SuperBIOS"
--------B-M00400076--------------------------
MEM 0040h:0076h - FIXED DISK - CONTROL BYTE {IBM documented only for XT}
Size: BYTE
Desc: loaded from the disk parameter table control byte (offset 8) during
various hard disk operations
See Also: MEM 0040h:0075h"FIXED DISK",MEM 0040h:0077h"FIXED DISK"
--------d-M00400076--------------------------
MEM 0040h:0076h - XT: hard disk controller's I/O address (Western Digital)
Size: BYTE
--------d-M00400076--------------------------
MEM 0040h:0076h - WD1002-27X SuperBIOS - USED IN TRACK RECALCULATION
Size: BYTE
See Also: MEM 0040h:0074h"SuperBIOS",MEM 0040h:0075h"SuperBIOS"
See Also: MEM 0040h:0077h"SuperBIOS"
--------B-M00400077--------------------------
MEM 0040h:0077h - FIXED DISK - I/O port offset {IBM documented only for XT}
Size: BYTE
See Also: MEM 0040h:0075h"FIXED DISK",MEM 0040h:0076h"FIXED DISK"
--------d-M00400077--------------------------
MEM 0040h:0077h - WD1002-27X SuperBIOS - USED IN TRACK RECALCULATION
Size: BYTE
See Also: MEM 0040h:0076h"SuperBIOS"
--------B-M00400078--------------------------
MEM 0040h:0078h - PARALLEL DEVICE 1 TIME-OUT COUNTER
Size: BYTE
See Also: MEM 0040h:0079h,MEM 0040h:007Ah,INT 17/AH=00h
--------B-M00400079--------------------------
MEM 0040h:0079h - PARALLEL DEVICE 2 TIME-OUT COUNTER
Size: BYTE
See Also: MEM 0040h:0078h,MEM 0040h:007Ah,INT 17/AH=00h
--------B-M0040007A--------------------------
MEM 0040h:007Ah - PARALLEL DEVICE 3 TIME-OUT COUNTER
Size: BYTE
See Also: MEM 0040h:0078h,MEM 0040h:0079h,MEM 0040h:007Bh"PARALLEL"
--------B-M0040007B--------------------------
MEM 0040h:007Bh - PARALLEL DEVICE 4 TIME-OUT COUNTER (pre-PS, PS Models 25,30)
Size: BYTE
See Also: MEM 0040h:0078h,MEM 0040h:007Ah,MEM 0040h:007Bh"INT 4Bh"
--------m-M0040007B--------------------------
MEM 0040h:007Bh - INT 4Bh FLAGS (PS2 and newer)
Size: BYTE
See Also: INT 4B/AX=8102h
Bitfields for INT 4Bh flags:
Bit(s) Description (Table M023)
7-6 reserved
5 set if Virtual DMA Spec supported [PS] (see INT 4B)
4 reserved
3 set if INT 4Bh intercepted and must be chained
2 reserved
1 set if Generic SCSI CBIOS services available on INT 4Bh
0 reserved
--------B-M0040007C--------------------------
MEM 0040h:007Ch - SERIAL DEVICE 1 TIMEOUT COUNTER
Size: BYTE
See Also: MEM 0040h:0000h,MEM 0040h:007Dh,MEM 0040h:007Eh,MEM 0040h:007Fh
See Also: INT 14/AH=01h
--------B-M0040007D--------------------------
MEM 0040h:007Dh - SERIAL DEVICE 2 TIMEOUT COUNTER
Size: BYTE
See Also: MEM 0040h:0002h,MEM 0040h:007Ch,MEM 0040h:007Eh,MEM 0040h:007Fh
See Also: INT 14/AH=01h
--------B-M0040007E--------------------------
MEM 0040h:007Eh - SERIAL DEVICE 3 TIMEOUT COUNTER
Size: BYTE
See Also: MEM 0040h:0004h,MEM 0040h:007Ch,MEM 0040h:007Dh,MEM 0040h:007Fh
See Also: INT 14/AH=01h
--------B-M0040007F--------------------------
MEM 0040h:007Fh - SERIAL DEVICE 4 TIMEOUT COUNTER
Size: BYTE
See Also: MEM 0040h:0006h,MEM 0040h:007Ch,MEM 0040h:007Dh,MEM 0040h:007Eh
See Also: INT 14/AH=01h
--------K-M00400080--------------------------
MEM 0040h:0080h - KEYBOARD BUFFER START OFFSET FROM SEGMENT 40h (normally 1Eh)
Size: WORD
See Also: MEM 0040h:001Ah,MEM 0040h:001Eh,MEM 0040h:0082h,INT 16/AH=05h
--------K-M00400082--------------------------
MEM 0040h:0082h - KEYBOARD BUFFER END+1 OFFSET FROM SEGMENT 40h (normally 3Eh)
Size: WORD
Note: XT BIOS dated 11/08/82 ends here
See Also: MEM 0040h:001Ch,MEM 0040h:003Eh,MEM 0040h:0080h,INT 16/AH=05h
--------V-M00400084--------------------------
MEM 0040h:0084h - VIDEO (EGA/MCGA/VGA) - ROWS ON SCREEN MINUS ONE
Size: BYTE
See Also: MEM 0040h:0085h
--------V-M00400085--------------------------
MEM 0040h:0085h - VIDEO (EGA/MCGA/VGA) - CHARACTER HEIGHT IN SCAN-LINES
Size: WORD
See Also: MEM 0040h:0084h
--------V-M00400087--------------------------
MEM 0040h:0087h - VIDEO (EGA/VGA) CONTROL: [MCGA: =00h]
Size: BYTE
See Also: MEM 0040h:0084h,MEM 0040h:0085h,MEM 0040h:0088h
Bitfields for EGA/VGA Video control flags:
Bit(s) Description (Table M024)
7 do not to clear RAM on mode set (see INT 10h, AH=00h)
6-5 RAM on adapter = (this field + 1) * 64K
4 reserved
3 EGA/VGA video system INactive
2 wait for display enable
1 mono monitor
0 alphanumeric cursor emulation DISabled
When enabled, text mode cursor size (INT 10,AH=01h) settings looking
like CGA ones are translated to equivalent EGA/VGA ones.
--------V-M00400088--------------------------
MEM 0040h:0088h - VIDEO (EGA/VGA) SWITCHES: [MCGA: reserved]
Size: BYTE
See Also: MEM 0040h:0087h,MEM 0040h:0089h
Bitfields for EGA/VGA Video switches:
Bit(s) Description (Table M025)
7-4 power-on state of feature connector bits 3-0
3-0 configuration switches 4-1 (=0 on, =1 off) (see #M026)
Note: when bit 4 of 0040h:0089h is 0, VGA emulates 350-line EGA if this
byte is x3h or x9h, otherwise emulates 200-line CGA in 400-line
double scan. VGA resets this byte to x9h after the mode set.
See also note for 0040h:0089h.
(Table M026)
Values for EGA/VGA configuration switches:
00h Pri MDA, Sec EGA+old color display 40 x 25
01h Pri MDA, Sec EGA+old color display 80 x 25
02h Pri MDA, Sec EGA+ECD normal mode (CGA emul)
03h Pri MDA, Sec EGA+ECD enhanced mode
04h Pri CGA 40 x 25, Sec EGA mono display
05h Pri CGA 80 x 25, Sec EGA mono display
06h Pri EGA+old color display 40 x 25, Sec MDA
07h Pri EGA+old color display 80 x 25, Sec MDA
08h Pri EGA+ECD normal mode (CGA emul), Sec MDA
09h Pri EGA+ECD enhanced mode, Sec MDA
0Ah Pri EGA mono display, Sec CGA 40 x 25
0Bh Pri EGA mono display, Sec CGA 80 x 25
See Also: #M025
--------V-M00400089--------------------------