IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

LOC (lBJ LINE SOURCE
3007 j --- INT 17 --------------------------------­
3006 ; PRIfHER_IO
3009 TliIS ROUTINE PROVIDES COMMUNICATION WITH THE PRINTER
3010 (AH)=O F'RIHT THE CHARACTER IN (All
3011 ON RETUIHI, AH=1 IF CHARACTER COULD NOT BE PRINTED (TIME OUT)
3012 OTHER BITS SET AS ON NORMAL STATUS CALL
3013 (AH)=1 INITIALIZE THE PRunER PORT
3014 RETURNS WITH (AH) SET WITH PRINTER STATUS
3015 (AH)=2 READ THE PRINTER STATUS INTO UH)
3016
3017 TIME OUT
3018
3019
51 i
t1. ,::1 ~~~~:D
3020 _ 1 ::. SElECTED
3021 1 '" OUT OF PAPER
3022 1 = ACKNOWLEDGE
'3023 1 = BUSY
3024
3025 (OX) = PRINTER TO BE USED (0.1.2) CORRESPONDING TO ACTUAL VALUES
3026 I IN PRINTER_BASE AREA
3027 ; DATA AREA PRINTER_BASE CONTAItIS THE BASE ADDRESS OF THE PRINTER CAROlS)
3028 AVAILABLE (LOCATED AT BEGINNWG OF DATA SEGMENT, 408H ABSOLUTE, 3 WORDS)
3029 ;REGISTER5 AH IS MODIfIED
3030 • ALL OTHERS UNCHANGED
3031 ; ---- ---------------------------------------­
3032 ASSUME CS: CODE ,DS:DATA
EF02 3033 PRINTER _10 PROC fAR
EFOZ Fe 3034 STI INTERRUPTS BACK ON
EF03 IE 3035 PUSH os j SAVE SEGMENT
EFD4 52 3036 PUSH OX
EFOS 56 3037 PUSH
5'
EF06 51 3038 PUSH CX
HD7 53 3039 PUSH ex
EFDB 8E4000 3040 NOV 51 ,DATA
EFDB BEDE 3041 NOV DS,SI ; ESTABLISH PRINTER SEGMENT
£FDD BaFl 3042- HOV SI,DX ; GET PRINTER PARM
EFOF 01E6 3043 5HL 51,1 ; WORD OFFSET INTO TABLE
EFEl 88940800 3044 HOV OX,PRINTER_BASE[SI) ; GET BASE ADDRESS FOR PRINTER CARD
EFES 0802 3045 OR OX,OX j TEST OX FOR ZERO, INDICATING NO PRINTER
EFE7 740C 3046 JZ Bl j RETURN
EFE9 0.6.£4 3047 OR AH,AH TEST FOR {AH )=0
EFEB 740£ 3048 JZ e. PRINT_AL
£FED FEee 3049 DEC AH TEST FOR CAH)=1
EFEF 7442 3050 JZ .B
INIT_PRT
EFFl FEee 3051 DEC AH TEST FOR (AH )::.2
EFF3 742.6. 3052- JZ 6S PR INTER STATUS
£FFS 3053 Bl : RETURN
EFF5 58 3054 POP ex
EFF6 S9 3055 POP ex
EfF7 5£ 3056 POP
5'
j RECOVER REGISTERS
EFFS 5A 3057 POP ox j RECOVER REGISTERS
EFF9 IF 3058 POP Os
EFFA CF 3059 IRET
3060
3061 j------ PRINT THE CHARACTER IN (ALI
3062­
EFF6 3063 82:
EFFB 50 3064 PUSH AX SAVE VALUe TO PRINT
EFfC 830A 3065 HOV st.IO TIME OUT VALUE
EFFE 33C9 3066 XOR ex,Cx ESTABLISH SHIFT COUNT
FOOD EE 3067 OUT DX,AL ; OUTPUT CHAR TO PORT
FOOl 42 3068 we ox ; PorNT TO STATUS PORT
FOOl 3069 83: ; WAIT_BUSY
FOOZ EC 3070 AL,DX ; GET STATUS
F003 8AEO 3071 r.OV
'"
AH,AL j STATUS TO AH ALSO
Foes A880 3072 TEST At,SOH ; IS TtfE PRINTER CURRENTLY BUSY
F007 750E 3073 Jt~Z 6. j OUT_STrlOBE
F009 EZF] 3074 LOOP 63 ; DECREMENT COUNT ON TIME OUT
FODe FEee 3075 DEC 6L
FOOD 75F3 3076 JHZ 63 ; WAIT FOR NOT BUSY
FOOF BOCCOI 3077 OR AH,l ; SET EPROR FLAG
FOl2 80E4F9 3078 Arm AH,OF9H ; TURN OFF THE OTHER BITS
Fots EBI4 3079 JHP 5HORT 87 ; RETUPtl WITli ERROR flAG SET
FOl7 30BO 84: ; OUT_STReBE
FOl7 BOOO 3081 HOV AL,OOH j SET THE STROBE HIGH
F019 42 3082 we DX ; STROBE IS BIT 0 OF PORT C OF 8255
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