IBM PC CONVERTIBLE

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