IBM PC CONVERTIBLE Technical Reference page 223

ASCII Conversion (STR_CON)
0275
0275 51
0276 B1 OC
******************************************************************
ROUTINE-NAME: STR_CON
FUNCTION: THIS ROUTINE CONVERTS HEX NUMBERS TO ASCII AND STORES
THEM AT ADDRESS ES: DI .
ENTRY CONDITIONS:
PURPOSE OF ENTRY: TO POST ERROR MESSAGES IN MEMORY
INPUT CONDITIONS: DX = HEX NUMBER TO BE CONVERTED
ES: DI
=
PLACE I N MEMORY TO PUT ASC I I STRNG
RESTRICTIONS: NONE
EXIT CONDITIONS:
NORMAL EXIT CONDITIONS:
ERROR EXIT CONDITIONS:
REGISTERS MODIFIED: CX,DX,ES,DI
INTERNALLY REFERENCED ROUTINES: NONE
EXTERNALLY REFERENCED ROUTINES: NONE
******************************************************************
STR_CON PROC NEAR
PUSH CX
MOV CL,12 ; CONVERT 2 BYTES
0278 26: C6 05 20 MOV BYTE PTR ES: [DI-, 020H ; INSERT ASCII BLANK
027C 47 INC DI INC POINTER
027D 52
SClO: PUSH DX
SAVE COUNT
027E D3 EA
SHR DX,CL
MOVE HIGH NIBBLE TO LOW NIB
0280 80 E2 OF
AND DL,OFH
MASK OUT NEW HIGH NIBBLE
0283 80 FA 09
CMP DL,09
ALPHA OR NUMERIC
0286 7E 03
JLE SC24
NO ADJUST FOR ALPHA
0288 80 C2 07 ADD
DL,07
ADJUST FOR ALPHA
028B 80 C2 30 SC24 : ADD DL ,30H CONVERT TO ASCI I
028E 26: 88 15 MOV ES:[DI],DL SEND ERROR TO SCREEN
0291 47
INC DJ
POINT TO NEXT MEMOERY LOCAT
0292
5A POP DX
RESTORE AX
0293 80 E9 04
SUB CL,4
SUB 4 FROM SH I FT COUNT
0296 80 F9 00
CMP CL,O
SEE I F MINUS
0299 7D E2
JGE SClO LOOP
029B
59
POP
CX
029C C3
SCRET: RET RETURN
029D STR_CON
ENDP
NMI Handler Entry Point Address
(NMI_INT)
; *************************************
NMI HANDLER ENTRY POINT ADDRESS
; *************************************
;ORG OE2C3H
02C3 ORG 002C3H
=
02C3
NMLJNT EQU
02C3 E9 0000 JMP NMLFLIH
2-198 ROM BIOS