IBM 5150 Hardware Reference Manual page 216

LOC OBJ LINE SOURCE
,,-...,
,,-...,
EiO! EC
E7DZ A82:0
E704 7508
E706 E2F9
E7D8
sa
E7D9 80ce80
E7ae Ee88
E7DE
E7Df 83EA05
E7El 59
E7EZ: 8ACl
E7£4 EE
E7E5 E97EFF
E7E8
E7E8 80Z671007F
E7ED 83C204
E7FO BOOI
E7n EE
E7F3 83C202
E1F6 2BC9
E7Fa
E7F8 EC
E7F9 AB20
E7FB 7507
E7FD E2F9
E7fF
E7FF 8480
EaCI E962FF
EB04
Ea04 4A
Eaos
ESOS EC
E806 A801
Eece 7509
EeCA F6067100eO
E80F 74F4
E811 EBEC
E813
EB13 241E
EB15 8AED
EBl7 88940000
E81B EC
E81C E947ff
E8lF
E81F 88940000
E823 83C205
E826 EC
E827 8AEO
E82:9 42
E82:A EC
E82B E938FF
1582
IN
AL,DX
; GET STATUS
158l
TEST
AL,ZOH
; IS TRANSMITTER READY
1584
JNZ
All
; OUT_CHAR
1585
LOOP AID ; GO BACK FOR MORE. AND TEST FOR TIME OUT
1586
POP AX ; RECOVER ORIGINAL INPUT
1587
OR AH.SOH
; SET THE TIME OUT BIT
1"8
JMP Al ; RETUWN
1589
All:
; OUT_CHAR
1590
SUB OX,S
" DATA PORT
1591 POP
ex
; RECOVER IN
ex
TEMPORARILY
1592
MOV AL,Cl ; GET OUT CHAR TO Al FOR OUT. STATUS IN AH
1593
OUT
DX,Al
; OUTPUT CHARACTER
1594 JMP Al ; RETURN
1595
1596
J------
RECEIVE CHARACTER FROM COMMO LINE
1597
1598 .1.12 :
1599
ANO
BIOS_BREAK. 07FH ; TURN OFF BREAK BIT IN BYTE
1600
ADO
DX,4
j
MODEM CON1ROl REGISTER
1601
MOV Al,! ; DATA TERMINAL READY
1602
OUT
OX,At
1603
ADO DX,2 ; MODEM STATUS REGISTER
1604 SUB CX,CX ; ESTABLISH TIME OUT COUNT
1605 A13: ; WAIT_DSR
1606
IN
Al,OX ; MODEM STATUS
1607
TEST Al,2OM ; DATA SET READY
1608 JNZ A1S ; IS IT READY YET
1609
LOOP
All
; WAIT UNTIL IT IS
1610 A14: ; TIME_OUT_ERR
1611
MOV
AH.80H ; SET TIME OUT ERROR
1612
JMP Al
J RETUPN WITH ERROR
1611 AIS: ; WAIT_OSR_ENO
1614
DEC OX
; LINE STATUS REGISTER
1615
A16: ; WAIT_RECV
1616
IN Al,OX ; GET STATUS
1617 TEST Alol J RECEIVE BUFFER FUll
)618
JNZ A17 ; GET CHAR
1619 TEST BIOS_BREAK,BOH J TEST FOR BREAK KEY
1620
JZ Alb
I
LOOP IF
~mT
)621
JMP A14 i SET TIME OUT ERROR
1622 A17: ; GET_CHAR
)623
AND Al,OOOl1110B
; TEST FOR ERROR CONDITIONS ON RECV CHAR
1624 MOV AH,Al ; SAVE THIS PART OF STATUS FOR LATER OPERATION
1625 MOV DX,RS232_BASE[ SI
J
; DATA PORT
1626 Al,DX ; GET CHARACTER FROH LINE
'"
1627
JMP Al
; RETURN
1628
1629
;------ COMMO PORT STATUS ROUTINE
1630
1631 A18:
1632 MOV OX ,RS232_BASE[SI
J
1633 ADO OX.S J CONTROL PORT
1634
IN
AL,OX ; GET LINE COHTROL STATUS
1635 MOV AH,Al
I
PUT IN AH FOR RETURN
1636 INC OX ; POINT TO MODEM STATUS REGISTER
1637 IN Al,OX
; GET MODEM CONTROL STATUS
1638
JMP Al
; RETURN
1639 RS232_IO ENOP
1640
; ---- INT 16 ------------------------------- ­
1641
i KEYBOARD I/O
1642:
THESE ROUTINES PROVIDE KEYBOARD SUPPORT
)643 ; INPUT
1644
I AHJ=O
READ THE NEXT ASCII CHARACTER STRUCK FROM THE KEYBOARD
1645 RETURN THE RESULT IN I AU, SCAN CODE IN (AH I
164& (AHJ=l SET THE Z FlAG TO INDICATE IF AN ASCII CHARACTER IS AVAIlABLE
1641 TO BE READ.
1648 (ZF )=1 -- NO COOE AVAILABLE
1649 (IF )=0 -- CODE IS AVAILABLE
1650 IF Zf
=
0, THE NEXT CHARACTE~ IN THE BUFftR TO BE READ IS
1651 IN AX, AtID THE ENTRY REMAINS IN THE BUFFER
1652 (AHI=2 RETURN THE CURRENT SHIFT STATUS IN AL PEGISTER
1653 THE BIT SETTINGS FOR THIS CODE ARE INDICATED IN THE
1654 THE EQUATES FOR KBJLAG
1655 ; OUTPUT
1656 AS NOTED ABOVE, OIRY AX Atm FLAGS CHANGED
1651 All REGISTERS RETAWED
1658
1--------- -- ----- -- --- --------------- --- ­
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