IBM PC CONVERTIBLE

SET CURSOR POSITION, AX HAS ROW/COLUMN FOR CURSOR
025B
025B
025E
0260
0264
0266
0268
026B
026C
E8 02E6 R
8B C8
03 OE 004E R
01 F9
B4 OE
E8 0228 R
C3
MI8
CALL
MOV
ADD
SAR
MOV
CALL
RET
MI8
PROC NEAR
POSITION
CX,AX
CX,CRLSTART
CX, I
AH,14
MI6
ENDP
FIND LOCATION IN REGEN BFR
ADD START ADDR FOR THIS PAGE
DIVIDE BY 2 FOR CHAR COUNT
REGISTER NUMBER FOR CURSOR
OUTPUT THE VALUE TO THE 6845
ACLDI SP _PAGE
INPUT
OUTPUT
026C
026C
A2 0062 R
026F 8B OE 004C R
0273 98
0274 50
0275 F7 El
0277 A3 004E R
027A 8B C8
027C 01 F9
027E B4 OC
0280 E8 0228 R
0283 5B
0284 01 E3
0286 8B 87 0050
028A E8 025B R
0280
E9 016F R
0290
THIS ROUTINE SETS THE ACTIVE DISPLAY PAGE, ALLOWING THE
FULL USE OF THE RAM SET ASIDE FOR THE VIDEO ATTACHMENT.
**** VALID ONLY FOR ALPHA MODES ****
AL HAS THE NEW ACTIVE DISPLAY PAGE
(0-7) FOR MODES 0&1, (0-3) FOR MODES 2&3, AND
(0) FOR MODE 7 WHEN MONOCHROME MONITOR
(0-3) FOR MODE 7 WHEN THE LCD IS CONFIGURED AS MONO
(OS) = DATA SEGMENT
THE 6845 IS RESET TO DISPLAY THAT PAGE
ACLDISP_PAGE
PROC NEAR
MOV
ACTIVE_PAGE,AL
SAVE ACTIVE PAGE VALUE
MOV CX,CRLLEN GET SAVED LEN OF REGEN BFR
CBW CONVERT AL TO WORD
PUSH AX SAVE PAGE VALUE
MUL CX DISPLAY PAGE TIMES REGEN LEN
MOV CRLSTART ,AX SAVE START ADDRESS FOR
LATER REQUIREMENTS
MOV CX,AX START ADDRESS TO CX
SAR CX, I DIVIDE BY 2 FOR 6845
MOV AH,12 6845 REGISTER FOR START ADDR
CALL MI6
POP BX RECOVER PAGE VALUE
SAL BX, I ; *2 FOR WORD OFFSET
MOV AX, [BX + OFFSET CURSOR_POSN- ; GET CURSOR FOR PAGE
CALL MI8 ; SET THE CURSOR POSITION
JMP
VIDEO_RETURN
ACLDISP_PAGE
ENDP
READ_CURSOR
INPUT
OUTPUT
0290
0290 8A OF
0292 32 FF
0294 01 E3
0296 8B 97 0050 R
029A 8B OE 0060 R
029E 55
029F 8B EC
02AI 89 56 OC
02A4 89 4E OA
02A7 50
02A8 E9 0l6F R
02AB
THIS ROUTINE READS THE CURRENT CURSOR VALUE FROM THE
6845, AND SENDS IT BACK TO THE CALLER
BH - PAGE OF CURSOR, MUST BE 0 FOR GRAPHICS
OS - DATA SEGMENT
OX - ROW, COLUMN OF THE CURRENT CURSOR POSITION
CX - CURRENT CURSOR MODE
READ_CURSOR PROC
NEAR
MOV BL,BH
XOR BH,BH
SAL BX, I ; WORD OFFSET
MOV OX, [BX+OFFSET CURSOILPOSN]
MOV CX, CURSOILMODE
PUSH BP
MOV BP ,SP
MOV [BP] . DLPOS, OX
MOV [BP] . CLPOS, CX
POP BP
JMP VIDEO_RETURN
READ_CURSOR ENDP
GET PTR TO STACK SAVE AREA
SETUP RETURN VALUES IN STACK
SAVE AREA
2-90 ROM BIOS