Atari 400 Technical Reference Manual page 284

ERR LINE ADDR
Bl B2 B3 B4
CENTRAL INPUT/OUTPUT (CIO) 2-7-79
PAGE 23
1000
,PAGE
1001
1002
i
WRITE -- DO PUT COMMANDS
1003
E5C9 A5 22 CIWRIT: LDA
ICCOMZ iGET COMMAND BYTE
1004 E5CB 25 2A
AND ICAXIZ
i
IS THIS WRITE LEGAL?
1005 E5CD
DO 05
BNE WCIIA
i
YES
1006
1007
ILLEGAL WRITE -- DEVICE OPENED FOR READ ONLY
1008 E5CF
AO 87 LDY #RDONLY
i
ERROR CODE
1009 E5D1
4C 1B E6 WC I 1B:
JMP CIRTN1 iRETURN
1010
i
1011
i
COMPUTE AND CHECK ENTRY POINT
1012 E5D4
20 3D E6 WC I lA: JSR COMENT
iCOMPUTE HANDLER ENTRY POINT
1013 E507 BO F8
BCS WCIIB
iGO
IF ERROR IN COMPUTE
1014
1015
i
PUT RECORD OR CHARACTERS
1016 E5D9 A5 28
LOA ICBLLZ
1017 E5DB 05 29
ORA ICBLLZ+l
i
IS BUFFER LENGTH ZERO?
1018 E5DD DO 06
BNE WCI3
iNa
1019 E5DF
A5 2F LOA CIOCHR
i
GET CHARACTER
1020 E5El E6 28
INC ICBLLZ iSET BUFFER LENGTH=1
1021 E5E3 DO 06
BNE WCI4 iTHEN JUST TRANSFER ONE BYTE
1022
i
1023
i
'LOOP TO TRANSFER BYTES FROM BUFFER TO HANDLER
1024
E5E5 AO 00 WCI3:
LOY
#0
1025 E5E7 B1 24
LOA (ICBALZ)
I
Y
iGET BYTE FROM BUFFER
1026 E5E9
85 2F STA CIOCHR
i
SAVE
1027 E5EB
20 89 E6 WCI4:
JSR GOHAND
i
GO PUT BYTE
1028 E5EE 30 25
BMI WCI5 iEND IF ERROR
1029 E5FO
20 70 E6
JSR INCBFP i INCREMENT BUFFER POINTER
1030
1031
CHECK FOR TEXT RECORD
1032 E5F3 A5 22
LDA ICCOMZ iGET COMMAND BYTE
1033 E5F5
29 02 AND #2
i IS IT PUT RECORD?
1034 E5F7 DO OC
BNE WCll iNa
1035
1036
TEXT RECORD -- CHECK FOR EOL TRANSFER
1037 E5F9 A5 2F
LDA CIOCHR iGET LAST CHARACTER
1038 E5FB C9 9B
CMP #EOL i IS IT AN EOL?
1039 E5FD DO 06
BNE WCIl
i NO
1040
E5FF 20 63 E6
JSR OECBFL iDECREMENT BUFFER LENGTH
1041 E602 4C 15 E6
JMP WCI5 iEND TRANSFER
1042
1043
i CHECK FOR BUFFER EMPTY
1044 E605 20 63 E6
WCll : JSR DECBFL
iDECREMENT BUFFER LENGTH
1045 E608
DO DB BNE WCI3
iCONTINUE IF NON ZERO