IBM PC CONVERTIBLE Technical Reference page 88

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OB6A
4A
DEC
OX
(XFA)
OB6B
4A
DEC
OX
ADDRESS BAUD MSB
(XF9)
OB6C
EC
IN
AL,DX
READ FROM 8250
OB6D
AA
STOSB
SAVE
OB6E
4A
DEC
OX
ADDRESS OTHER BAUD BYTE
(XF8)
OB6F
EC
IN
AL,DX
READ FROM 8250
OB70
AA
STOSB
SAVE
OBll
C3
RET
EXIT
OB72
83 C7 06
ASI :
ADD
01,6
SKIP OVER DATA AREA
OB75
C3
RET
EXIT
; -----RESUME COMMAND
OB76
ASLRESUME:
OB76
22 CO
AND
AL,AL
IS PORT OPERATING?
OB78
74 2F
JZ
AS2
NO, DO NOT RESTORE
OB7A
AC
LODSB
YES, LOOK AT STORED DATA
OB7B
3C AA
CMP
AL,GOOD_DATA
IS IT GOOD?
OB7D
75 2B
JNE
AS3
NO, DO NOT RESTORE
YES, SO RESTORE 8250
OB7F
AC
LODSB
GET LINE CONTROL REG FROM RAM
OB80
50
PUSH
AX
STORE ON STACK
OB81
42
INC
OX
(XF9)
OB82
42
INC
OX
(XFA)
OB83
42
INC
OX
ADDRESS LINE CTL REG (XFB)
OB84
2A CO
SUB
AL,AL
SET DLAB BIT 0
OB86
EE
OUT
DX,AL
TO ALLOW NORMAL ADDRESS I NG
OB87
42
INC
OX
ADDRESS MODEM CONTROL REG (X FC)
OB88
AC
LODSB
GET FROM RAM
OB89
EE
OUT
DX,AL
AND RESTORE 8250
OB8A
42
INC
OX
(XFO)
OB8B
42
INC
OX
(XFE)
OB8C
42
INC
OX
ADDRESS SCRATCH REG
(XFF)
OB8D
AC
LODSB
GET FROM RAM
OB8E
EE
OUT
DX,AL
AND WRITE TO 8250
OB8F
83 EA 07
SUB
DX,7
ADDRESS DATA REG
(XF8)
OB92
EC
IN
AL,DX
GET ANY TRASH CHRS
OB93
EC
IN
AL,DX
OB94
42
INC
OX
ADDRESS I NTR CTL REG (XF9)
OB95
AC
LODSB
GET FROM RAM
OB96
EE
OUT
DX,AL
AND WRITE TO 8250
OB97
42
INC
OX
(XFA)
OB98
42
INC
OX
ADDR LINE CONTROL REG(XFB)
OB99
BO 80
MOV
AL ,80H
SET DLAB BIT
=
1
OB9B
EE
OUT
DX,AL
IN 8250
OB9C
4A
DEC
OX
(XFA)
OB9D
4A
DEC
OX
(XF9)
OB9E
AC
LODSB
GET BAUD MSB FROM RAM
OB9F
EE
OUT
DX,AL
AND INTO 8250
OBAO
4A
DEC
OX
ADDR BAUD LSB
(XF8)
OBAI
AC
LODSB
GET FROM RAM
OBA2
EE
OUT
DX,AL
AND INTO 8250
OBA3
42
INC
OX
(XF9)
OBA4
42
INC
OX
(XFA)
OBA5
42
INC
OX
ADORE LINE CONTROL AGAIN (XFB)
OBA6
58
POP
AX
PULL OFF STACK
OBA7
EE
OUT
DX,AL
AND PUT IN 8250
OBA8
C3
RET
OBA9
46
AS2:
INC
SI
CORRECT ADDRESS COUNT
o
BAA
83 C6 06
AS3:
ADD
SI,6
OBAD
C3
RET
ROM BIOS 2-63

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