Specifications

MICROPROCESSADORES
INTERRUPÇÕES
5
Luís Miguel Charrua Figueiredo 5 - 5 E.N.I.D.H.
against older versions or unsupported video modes, programs which expect to use
this function on EGA systems should set the ES:DX buffer to FFh before calling.
SeeAlso
: AX=1002h,AX=1007h,AX=CD02h
INT 10 - VIDEO - GET VIDEO DAC COLOR-PAGE STATE (VGA)
AX = 101Ah
Return
: BL = paging mode
00h four pages of 64
01h sixteen pages of 16
BH = current page
SeeAlso
: AX=1013h
INT 10 - VIDEO - PERFORM GRAY-SCALE SUMMING (VGA/MCGA)
AX = 101Bh
BX = starting palette register
CX = number of registers to convert
Return
: nothing
Desc
: convert the RGB values of one or more palette registers such that the
resulting values are grays with the same intensities as the original colors
SeeAlso
: AH=12h/BL=33h
INT 11 - BIOS - GET EQUIPMENT LIST
Return: (E)AX = BIOS equipment list word (see #00226,#03215 at INT 4B"Tandy")
Note
: since older BIOSes do not know of the existence of EAX, the high
word of EAX should be cleared before this call if any of the high bits will be tested
SeeAlso
: INT 4B"Tandy 2000",MEM 0040h:0010h
Bitfields for BIOS equipment list:
Bit(s) Description (Table 00226)
0 floppy disk(s) installed (number specified by bits 7-6)
1 80x87 coprocessor installed
3-2 number of 16K banks of RAM on motherboard (PC only)
number of 64K banks of RAM on motherboard (XT only)
2 pointing device installed (PS)
3 unused (PS)
5-4 initial video mode
00 EGA, VGA, or PGA
01 40x25 color
10 80x25 color
11 80x25 monochrome
7-6 number of floppies installed less 1 (if bit 0 set)
8 DMA support installed (PCjr, Tandy 1400LT)
DMA support *not* installed (Tandy 1000's)
11-9 number of serial ports installed
12 game port installed
13 serial printer attached (PCjr)
internal modem installed (PC/Convertible)
15-14 number of parallel ports installed
---Compaq, Dell, and many other 386/486 machines--
23 page tables set so that Weitek coprocessor addressable in real mode
24 Weitek math coprocessor present
---Compaq Systempro---
25 internal DMA parallel port available
26 IRQ for internal DMA parallel port (if bit 25 set)
0 = IRQ5
1 = IRQ7
28-27 parallel port DMA channel
00 DMA channel 0
01 DMA channel 0 ???
10 reserved
11 DMA channel 3
Notes
: Some implementations of Remote (Initial) Program Loader
(RPL/RIPL) don't set bit 0 to indicate a "virtual" floppy drive, although the RPL
requires access to its memory image through a faked drive A:. This may have
caused problems with releases of DOS 3.3x and earlier, which assumed A: and B:
to be invalid drives then and would discard any attempts to access these drives.
Implementations of RPL should set bit 0 to indicate a "virtual" floppy.
The IBM PC DOS 3.3x-2000 IBMBIO.COM contains two occurences of code
sequences like:
INT 11h
JMP SHORT skip
DB 52h,50h,53h; "RPS"
skip: OR AX,1
TEST AX,1
While at the first glance this seems to be a bug since it just wastes memory and
the condition is always true, this could well be a signature for an applyable patch
to stop it from forcing AX bit 0 to be always on. MS-DOS IO.SYS does not contain
these signatures, however.
BUGs
: Some old BIOSes didn't properly report the count of floppy drives
installed to the system. In newer systems INT 13h/AH=15h can be used to
retrieve the number of floppy drives installed. Award BIOS v4.50G and v4.51PG
erroneously set bit 0 even if there are floppy drives installed; use two calls to INT
13/AH=15h to determine whether any floppies are actually installed
SeeAlso
: INT 12"BIOS",#03215 at INT 4B"Tandy 2000"
INT 12 - BIOS - GET MEMORY SIZE
Return: AX = kilobytes of contiguous memory starting at absolute address 00000h
Note
: this call returns the contents of the word at 0040h:0013h; in PC and
XT, this value is set from the switches on the motherboard
SeeAlso
: INT 11"BIOS",INT 2F/AX=4A06h,INT 4C"Tandy 2000",MEM
0040h:0013h
INT 13 - DISK - RESET DISK SYSTEM
AH = 00h
DL = drive (if bit 7 is set both hard disks and floppy disks reset)
Return
: AH = status (see #00234)
CF clear if successful (returned AH=00h)
CF set on error
Note
: forces controller to recalibrate drive heads (seek to track 0) for PS/2
35SX, 35LS, 40SX and L40SX, as well as many other systems, both the master
drive and the slave drive respond to the Reset function that is issued to either
drive
SeeAlso
: AH=0Dh,AH=11h,INT 21/AH=0Dh,INT 4D/AH=00h"TI Professional"
SeeAlso
: INT 56"Tandy 2000",MEM 0040h:003Eh
INT 13 - DISK - GET STATUS OF LAST OPERATION
AH = 01h
DL = drive (bit 7 set for hard disk)
Return
: CF clear if successful (returned status 00h)
CF set on error
AH = status of previous operation (see #00234)
Note
: some BIOSes return the status in AL; the PS/2 Model 30/286 returns
the status in both AH and AL
SeeAlso
: AH=00h,INT 4D/AH=01h,MEM 0040h:0041h,MEM 0040h:0074h
(Table 00234)
Values for disk operation status:
00h successful completion
01h invalid function in AH or invalid parameter
02h address mark not found
03h disk write-protected
04h sector not found/read error
05h reset failed (hard disk)
05h data did not verify correctly (TI Professional PC)
06h disk changed (floppy)
07h drive parameter activity failed (hard disk)
08h DMA overrun
09h data boundary error (attempted DMA across 64K boundary or >80h
sectors)
0Ah bad sector detected (hard disk)
0Bh bad track detected (hard disk)
0Ch unsupported track or invalid media
0Dh invalid number of sectors on format (PS/2 hard disk)
0Eh control data address mark detected (hard disk)
0Fh DMA arbitration level out of range (hard disk)
10h uncorrectable CRC or ECC error on read
11h data ECC corrected (hard disk)
20h controller failure
31h no media in drive (IBM/MS INT 13 extensions)
32h incorrect drive type stored in CMOS (Compaq)