IBM AT 5170 Technical Reference page 313

IBM Personal Computer MACRO AS.!Iembler Version 2.00
1-2
RS232 ---- 06/10/e5 COMMUNICATIONS BIOS (RS23Z) 06-10-85
114
115
lib
1 17 0032
1 18 0032 8,0, EO
119 003483 C2 03
120 0037 BO 80
121 0039 EE
122
123
124
125 003,0. 8A 04
126 003C Bl 04
127 003E 02 C2
128 0040 81 E2 OOOE
129 0044 SF 0000 E
130 0047 03 FA
131 0049 88 94 0000 R
132 004D 42
133 004E 2E: 8A 45 01
134 0052 EE
135 0053 4A
136 0054 EB 00
137 0056 2E: SA 05
138 0059
EE
139 005A 83 C2 03
140 0050 8,0, C4
141 005F 24
IF
142 0061 EE
143 0062 4,0,
144 0063 4,0,
145 0064 EB 00
146 0066 80 00
147 0068 EE
148 0069 E8 48
149
150
151
152 0068
153 006B 50
154 006C 83 C2
155 006F BO 03
156 0071 EE
157 0072 42
158 0073 42
159 0074 87 30
160 0076 E8 00C5 R
161 0079 74
as
162 0078
163 0078 59
164 001e 8,0. CI
165 007E
166 007E 80 CC 80
167 0081
EB
,0,8
lb.
169 0083
170 0083 4,0,
171 0084
172 0084 81 20
173 0086 E8 00C5 R
174 0089 75 FO
175 00S8
176 008B 83 EA 05
177 008E 59
178 008F 8,0, CI
179 0091 EE
180 0092
E8
97
I . ,.2 I
'.3
184 0094
185 0094 83 C2 04
186 009780 01
187 0099 EE
188 009,0, 42
189 0098 42
190 009C
191 009C 87 20
192 009E ES DOCS R
193 00,0.1 1508
194 00,0.3
195 00,0.3 4,0,
196 00,0,4
197 00,0.4 B7 01
198 00A6 E8 00C5 R
199 00,0,9 75 03
200 00,0,8
201 00A8 80 E4 IE
202
203 OOAE 88 94 0000 R
204 0082 EC
205 00B3 E9 0028 R
20b
207
20.
209 00B6
210 0086 8B 94 0000 R
211 008,0. 83 C2 05
212 OOBD EC
213 OOBE 8,0, EO
214 OOCO
4Z
215 OOCI EC
216 00C2 E9 0028 R
PAGE
;-----
INITIALIZE THE COMMUNICATIONS FORT
,0.4:
MOV AH,AL
SAVE INITIALIZATION PARAMETERS IN (AHI
AOO DX,3
POINT TO 8250 CONTROL REGI STER
MOV AL,80H
OUT DX,AL SET DLA8='
DETERM I NE 8AUD RATE D I V I SOR
MOV
DL,AH
GET PARAMETERS TO lOLl
MOV
CL,4
ROL DL,CL
ANa OX,OEH I SOLA TE THEM
MOV DI ,OFFSET AI BASE OF TABLE
AOO
DI,DX ; PUT INTO INDEX REGISTER
MOV
DX,II!IRS232 8ASE(S]] ; POINT TO HIGH ORDER OF DIVISOR
INC
ox ­
MOV AL.CS: {DI]+ 1 GET HIGH ORDER OF OIVISOR
OUT DX,AL
SET ms OF DIVISOR TO 0
OEC
ox
JMP I/O DELAY
MOV AL,eS: [01
J
GET LOW ORDER OF D I V I SOR
'-2
OUT aX,AL
SET LOW OF DIVISOR
AOO
OX,3
MOV
AL,AH GET PARAMETERS BACK
ANa
AL,OIFH
STRIP OFF THE BAUD BITS
OUT DX,AL LINE CONTROL TO 8 BITS
OEC
ox
OEC
ox
JMP
I/O DELAY
,-2
MOV
AL,O
OUT
DX,AL
I NTERRUPT ENABLES ALL OFF
JMP SHORT ,0.18 COM_STATUS
SEND CHARACTER IN (AL) OVER COMMO LINE
AS:
PUSH SAVE CHAR TO SEND
AOO DX,4 MODEM CONTROL REG
I
STER
MOV AL,3 DTR AND RTS
OUT DX,AL DATA TERMINAL READY, REQUEST TO SEND
INC
ox
MODEM STATUS REGISTER
INC
ox
MOV
8H,30H
OAT A SET READY & CLEAR TO SEND
CALL WAIT FOR STATUS ARE BOTH TRUE
JE
'9 -
YES, READY TO TRANSMI T CHAR
,0,7:
POP
ex
MOV AL,CL
I
RELOAD DATA BYTE
OR AH,80H INDICATE TIME OUT
JMP A3
RETURN
A9: CLEAR TO SEND
DEC OX LINE STATUS REGISTER
AIO:
WAIT SEND
MOV BH,20H
IS TRANSM I TTER READY
CALL WA I T FOR STATUS TEST FOR TRANSMITTER READY
..JNZ ,0.7-
RETURN 'It 1 TH TIME OUT SET
AI I : OUT CHAR
SUB OX,S DATA PORT
POP CX RECOVER IN CX TEMPORAR I L Y
MDV AL,CL
MOVE CHAR TO AL FOR OUT, S T A TUS IN AH
OUT DX,AL OUTPUT CHARACTER
..JMP A3
RETURN
( - - - - ­
RECE 1 VE CHARAC1ER FROM COMNO LINE
,0.121
ADD DX,4 MODEM CONTROL REG I STER
MOV AL,I DATA TERM
1
NAL READY
OUT DX,AL
INC
ox
MODEM STATUS REGISTER
INC
ox
A13;
WAIT DSR
MOV 8H,20H DATA-SET READY
CALL WA
IT
FOR STATUS
TEST FOR DSR
..JNZ ,0,8 - ­
RETURN WITH ERROR
A151 WAIT DSR END
ox
LINE-STATUS REGISTER
A16: WA I T RECV
MOV BH,I
RECEIVE BUFFER FULL
CALL WA I T FOR STATUS TES T FOR RECE
1
VE BUFFER FULL
- ..JNZ ,0,8 -
SET T I ME OUT ERROR
A I 7:
GET CHAR
AND AH,OOOII t lOB TEST FOR ERROR CONDITIONS ON RECEIVE
MOV DX,IPRS232 BASE[S!] DATA PORT
IN A L , D X - GET CHARACTER FROM LINE
JMP ,0.3
RETURN
;-----
COMMa PORT STATUS ROUT INE
A
18:
MOV DX,<l'IRS232 BASE[SI]
ADD OX,5 - CONTROL PORT
IN AL,OX
GET LINE CONTROL STATUS
MOV AH,AL PUT IN (AH) FOR RETURN
INC
ox
POINT TO MODEM STATUS REGI STER
IN AL,DX GET MODEM CONTROL STATUS
..JMP ,0,3
RETURN
RS232
5-141