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

lOC 08J LINE SOURCE
F376 fBED 3834 JMP N14
3835 SCROL~OO!J:N ENDP
3836 ; ----------------------- ------------------­
3837 ; READ_At_CURRENT
3838 THIS ROUTINE READS THE ATTRIBUTE AND CHARACTER AT THE CURRENT
3839 CURSOR POSITION AHO RETURNS THEM TO THE CALLER
3a40
; INPUT
3841 (AH) :: CURRENT CRT t10DE
3842 (8H) :: DISPLAY PAGE ( ALPHA HODES ONLY 1
3843 (as) = DATA SEGMENT
3844 (ES) = REGEN SEGMENT
3845 ;OUTPUT
3846 (ALI = CHAR READ
3347 (AH) :: ATTRIBUTE READ
3848 ; -------------------- - - -------------------­
3849 ASSUME CS:CQDE.DS:DATA.ES:DATA
F37D 3850 READ_AC_CURRENT PROt NEAR
F37C 80FC04 3851 eMP AH,4 ; IS THIS GRAPHICS
n80 7Z0B 3852 JC PI
f382 80FC07 3853 CMP AH.7 ; IS THIS ew CARD
F38S 7403 3854 JE PI
Fl87 E9A902 3855 JMP GRAPHICS_READ
FlSA 3856 PI: ; READ_AC_CONTINUE
F3eA E81,o..OO 3857 CALL FINO_POSITION
F38D 8BF3 3858 MOV SI,ex j ESTABLISH ADDRESSING IN 51
3659
3S60
3861
j------ WAIT FOR HORIZONTAL RETRACE
F3SF 8BI66300 3862 MOV DX.AOOR_6845 ; GET BASE ADDRESS
F393 83C206 3863 ADD OX.6 i POINT AT STATUS PORT
F396 06 3864 PUSH ES
F397 IF 386$ POP OS ; GET SEGMENT FOR QUICK ACcESS
F398 3866 P2 : ; W.IT FOR RETR.CE LOW
F398 EC 3867 IN AL,OX ; GET STATUS
F399 ,0..801 3868 TEST AL,1 ; IS HaRZ RETRACE LOW
f39B 75FB 3869 JNZ P2 ; WAIT UNTIL IT IS
F39D FA 3870 CLI j NO MORE INTERRUPTS
r'\
F39E 3871 P3: ; WAIT FOR RETRACE HIGH
F39E EC 3872 IN AL.OX ; GET STATUS
f39F ,0..801 3873 TEST AL.! ; IS IT HIGH
FlAl 74F8 3874 JZ P3 ; WAIT UNTIL IT IS
FlA.3 AD 3875 lOOSW ; GET THE CHAR/ATTR
F3A4 E9Z0Ff 3876 JMP VIDEO_RETURN
3877 RE.O_AC_CURREHT ENDP
3878
FlA7 3879
nA7 8ACF 3880 MQV CL,BH ; DISPLAY PAGE TO CX
F3A9 3ZED 3881 XOR CH.CH
FlAB 86Fl 3882 NOV 5I.CX ; MOVE TO SI fOR INDEX
F3AO DIE6 3883 SAL 51.1 ; • 2: FOR WORD OFFSET
F3AF 88845000 3884 I10V AX,[SI+ OFFSET CURSOR]OSNJ ; GET ROW/COLUMN OF THAT PAGE
F3B3 330B 3885 XOR ex.ex SET START ADDRESS TO ZERO
F3BS n06 3686 JCXZ P5
nB7 3887 P4:
F367 031£4COO 3888 ADD BX.CRT_LEN LENGTH Of BUFfeR
FlBB EZFA 3889 lOOP P4
FlBD 3890 ps: ; NO_PAGE
F3BD E8CBFE 3891 CALL POSITlON ; DETERMINE LOCATION IN REGEN
nco 0308 3892 AOO BX.AX ; ADD TO START OF REGEN
F3C2 C3 3893 RET
3694 FINO_POSITION Et.'OP
3895 ; ----- ~----------- -----------------------­
3896 ;WRITE_AC_CURRENT
3897 THIS ROUTINE WRITES THE ATTRIBUTE AND CHARACTER AT
3696 THE CURRENT CURSOR POSITION
38'99 ; INPUT
3'900 ! AH) = CURRENT CRT MODE
3901 (BH) = DISPLAY PAGE
3902 (CXl = COUNT OF cHARACTERS TO WRITE
3903 (AU = CHAR' TO WRITE
3904 tBLl = ATTRIBUTE Of CHAR TO WRITE
3905 CDS) .. DATA SEGMENT
3906 (ES) = REGEN SEGMENT
3907 ;OUTPUT
3908 NONE
3909 ; --------- ------------- ---------------------­
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