IBM XT 5160 Technical Reference page 263

LOC OB.JECT LINE SOURCE (BIOS FOR THE IBM PERSONAL COMPUTER XTl 11/08/82
; ----- READ/WR I TE THE 8088 GENERAL AND SEGMENTAT I ON REG I STERS
WITH ALL ONE'S AND ZEROES'S.
SEL TIMER I,LSB,MODE 2
<><> <><> <> <><><> <> <> <><>
<><><>CHECKPO I NT 2<><><>
o
I SABLE DMA CONTROLLER
HALT SYSTEM I F ERROR
SET UP DATA SEG TO POINT TO
ROM ADDRESS
SET DIRECTION FLAG TO INC.
SETUP START I NG ROS ADDR
SETUP RETURN ADDRESS
ZERO IN AL ALREADY
o
I SABLE NM I INTERRUPTS
I NIT I ALZE DMA PAGE REG
o
I SABLE COLOR V IDEO
ENABLE PAR I TY CHECKERS AND
PULL KB CLOCK HI, TRI-STATE
KEYBOARD INPUTS, ENABLE HIGH
BANK OF SWITCHES->PORT C(0-3)
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<><><>CHECKPO I NT 1<><><>
SETUP SS SEG REG
DISABLE B/W VIDEO,EN HIGH RES
SET 8255 FOR B, A=OUT, C= IN
TST1A
ZERO PATTERN MAKE IT THRU?
YES - GO TO NEXT TEST
HAL T SYSTEM
SETUP ONE'S PATTERN IN AX
WR I TE PATTERN TO ALL REGS
TSTI A
PATTERN MAKE IT THRU ALL REGS
NO - GO TO ERR ROUT I NE
GO TO ERR ROUT I NE IF CF NOT SET
GO TO ERR ROUT I NE IF ZF NOT SET
GO TO ERR ROUT I NE IF PF NOT SET
GO TO ERR ROUT I NE I F SF NOT SET
LOAD FLAG I MAGE TO AH
LOAD CNT REG WITH SH I FT CNT
SH I FT AF I NTO CARRY BIT POS
GO TO ERR ROUT I NE IF AF NOT SET
SET THE OF FLAG ON
SETUP FOR TEST I NG
GO TO ERR ROUT I NE I F OF NOT SET
SET AH = 0
CLEAR SF, CF, ZF, AND PF
GO TO ERR ROUTINE IF CF ON
GO TO ERR ROUTINE IF ZF ON
GO TO ERR ROUTINE IF SF ON
GO TO ERR ROUTINE IF PF ON
LOAD FLAG I MAGE TO AH
LOAD CNT REG WITH SH I FT CNT
SHIFT 'AF' INTO CARRY BIT POS
GO TO ERR ROUTINE IF ON
CHECK THAT' OF ' I S CLEAR
GO TO ERR ROUTINE IF ON
o
I SABLE INTERRUPTS
SET SF, CF, ZF, AND AF FLAGS ON
AL,54H
TIMER+3,AL
AL,02H
PORT A,AL
AL,04
DMA08, AL
SS :CODE
BX,OEOOOH
SP, OFFSET C 1
ROS CHECK SUM
ERROl
AL,OIH
PORT A,AL
AX,CS
SS,AX
DS,AX
PORT_B,AL
OAOH,AL
83H,AL
DX,3D8H
DX,AL
AL
DL,OB8H
DX,AL
AL,89H
CMD PORT ,AL
AL,ToI0010lB
CL,5
AH,CL
ERROl
AH,I
ERROl
ERROl
ERRO I
ERROl
AH,OD5H
CL,5
AH,CL
ERROl
AL,40H
AL,
I
ERRO I
AH,AH
CS :CODE
,os
:NOTHING,ES :NOTH lNG, SS :NOTH ING
OE05BH
FAR
ERROl
ERROl
ERROl
ERRO I
AX,DI
CIO
AX,OFFFFH
DS,AX
BX,DS
ES,BX
CX,ES
SS,CX
DX,SS
SP,DX
BP,SP
SI,BP
DI,SI
C9
AX,DI
ERROl
C8
.JS
.JP
LAHF
MOV
SHR
.JC
SHL
.JO
MOV
OUT
MOV
OUT
MOV
OUT
CLD
ASSUME
MOV
MOV
.JMP
.JNE
OUT
MOV
OUT
MOV
MOV
MOV
OUT
OUT
MOV
OUT
INC
MOV
OUT
MOV
OUT
MOV
OR
.JZ
HLT
MOV
STC
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
.JNC
XOR
.JNZ
CLC
.JMP
ASSUME
ORG
LABEL
CLI
MOV
SAHF
.JNC
.JNZ
.JNP
.JNS
LAHF
MOV
SHR
.JNC
MOV
SHL
.JNO
XOR
SAHF
.JBE
8231 DMA INITIALIZATION CHANNEL REGISTER TEST
DESCR I PT I ON
DISABLE THE 8231 DMA CONTROLLER. VERIFY THAT
T I MER 1 FUNCT IONS OK. WR I TE
1
READ THE CURRENT
ADDRESS AND WORD COUNT REG I STERS FOR ALL
CHANNELS. I N I TI ALI ZE AND START DMA FOR MEMORY
REFRESH.
ROS CHECKSUM TEST I
DESCR I PT I ON
A CHECKSUM I S DONE FOR THE 8K
ROS MODULE CONTA I N I NG POD AND
BIOS.
8088 PROCESSOR TEST
DESCR I PT I ON
VER I FY 8088 FLAGS, REG I STERS
AND COND I T 10NAL .JUMPS
;----- VERIFY THAT TIMER 1 FUNCTIONS OK
; - - - - - 0 I SABLE DMA CONTROLLER
CII:
.
----------------------------------------
CIO:
ERRO I:
RESET
START:
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E019 1832
E01B 1A30
E01D 9F
E01E BI05
E080 D2EC
E082 1229
E084 DOE4
E086 1025
E088 B8FFFF
E08B F9
E08C 8ED8
E08E 8CDB
E090 8EC3
E092 8CC 1
E094 8EDI
E096 8CD2
£':098 8BE2
E09A 8BEC
E09C 8BF5
E09E 8BFE
EOAO 1301
EOA2 33C1
EOA4 1501
EOA6 F8
EOA1 EBE3
EOA9
EOA9 OBC1
EOAB 1401
EOAD F4
EOCE BBOOEO
EODI BCI6EO
EOD4 E91 BI8
EOD1 1504
EOD9 B002
EODB E660
EODD B004
EODF E608
EOC3 BOO I
EOC5 E660
EOC1 8CC8
EOC9 8EDO
EOCB 8ED8
EOCD FC
EOEI B054
EOE3 E643
EOAE
EOC I E661
EOAE E6AO
EOBO E683
EOB2 BAD803
EOB5 EE
EOB6 FECO
EOB8 B2B8
EOBA EE
EOBB B089
EOBD E663
EOBF BOA5
E05B
E05B
E05B FA
E05C B4D5
E05E 9E
E05F 134C
E061 154A
E063 1B48
E065 1946
E061 9F
E068 B 105
E06A D2EC
E06C 133F
E06E B040
E010 DOEO
E0121139
E014 32E4
E016 9E
E011 1634
5-116
PC-XT System BIOS (11/08/82)