IBM PC CONVERTIBLE

0764 74 57
0766 3C 07
0768 74 5A
JE
CMP
JE
UlO
AL,07H
Ull
LINE_FEED
IS IT A BELL
BELL
; ----- WRITE THE CHAR TO THE SCREEN
076A B4 OA
076C B9 0001
076F CD 10
0771 FE C2
0773 3A 16 004A R
0777 75 33
0779 B2 00
077B 80 FE 18
077E 75 2A
0780
0780
B4 02
0782 CD 10
0784 AO 0049
0787
3C 04
0789 72 06
078B 3C 07
0780 B7 00
078F 75 06
0791
0791
B4 08
0793 CD 10
0795 8A FC
0797
0797
B8 0601
079A 2B C9
079C B6 18
079E 8A 16 004A R
07A2 FE CA
07M
07M
CD 10
07A6
07A6 58
07A7 E9 016F R
07AA
07AA FE C6
07AC
07AC B4 02
07AE EB F4
MOV
MOV
INT
AH,WRITE_CHAILONLY
CX,l
VIDEO_FN
WRITE CHAR ONLY TO ACTIVE PG
ONLY ONE CHARACTER
INT 10H
POSITION THE CURSOR FOR NEXT CHAR
INC
CMP
JNZ
MOV
CMP
JNZ
DL
DL, BYTE PTR CRLCOLS ; TEST FOR COLUMN OVERFLOW
U7 SELCURSOR
DL,O COLUMN FOR CURSOR
DH,24
U6 SELCURSOR_INC
SCROLL REQUIRED
U1:
MOV
INT
AH,SELCURSOR_POS ; SET THE CURSOR
VIDEO_FN
DETERMINE VALUE TO FILL WITH DURING SCROLL
U2:
U3 :
U4:
MOV
CMP
JC
CMP
MOV
JNE
MOV
INT
MOV
MOV
SUB
MOV
MOV
DEC
INT
U5 :
POP
JMP
U6:
INC
U7:
MOV
JMP
AL,cn .. .MODE
AL,4
U2
AL,7
BH,O
U3
AH, READ.J\ TLCHAR
VIDEO_FN
BH,AH
GET THE CURRENT MODE
READ-CURSOR
FI LL WITH BACKGROUND
SCROLL-UP
READ-CURSOR
READ CHAR/ATTR AT CURSOR
I NT 10H
STORE IN BH
; SCROLL-UP
AX,SCROLL_WINDOW_UP*256+01H ; SCROLL UP ONE LINE
CX, CX ; UPPER LEFT CORNER
DH,24 ; LOWER RIGHT ROW
DL,BYTE PTR CRLCOLS ; LOWER RIGHT COLUMN
DL
VIDEO_FN
AX
VIDEO_RETURN
DH
AH, S ELCURSOR_POS
U4
V I DEO-CALL-RETURN
PROCESS VIDEO FUNCTION
TTY-RETURN
RESTORE THE CHARACTER
RETURN TO CALLER
SET-CURSOR-INC
NEXT ROW
SET -CURSOR
SET CURSOR POSITION
ESTABLISH THE NEW CURSOR
BACK SPACE FOUND
BACK SPACE DOES NOT BACK SPACE TO PREVIOUS LINE I F AT BEG OF LINE
07BO
07BO 80 FA 00
07B3 74 F7
07B5 FE CA
07B7 EB F3
07B9
07B9
B2 00
07BB EB EF
07BD
07BD 80 FE 18
U8:
CMP
JE
DEC
JMP
DL,O
U7
DL
U7
CARRIAGE RETURN FOUND
U9 :
MOV
JMP
DL,O
U7
LINE FEED FOUND
U10:
CMP DH,24
ALREADY AT BEGINNING OF LINE
SELCURSOR
NO -- JUST MOVE IT BACK
SELCURSOR
MOVE TO FI RST COLUMN
SELCURSOR
BOTTOM OF SCREEN
ROM BIOS 2-107