IBM 5150 Hardware Reference Manual page 255

LOC OBJ
LINE SOURCE
F689 57
4511 PUSH
01
i SAVE CODE POINTER
F68A B90800
4512
MOV
(x.a
i NUMBER OF BYTES TO MATCH
F66D F3
4513 REPE
CMPSB COMPARE THE 8 BYTES
f68E A6
F68F SF 4514 POP 01
RECOVER THE POINTERS
f690 Sf
4515 POP
51
F691 741E 4516 JZ 518
J IF ZERO FLAG SET, THEN MATCH OCCURRED
F693 FEeo 4517 INC
AL ; NO MATCH, MOVE ON TO NEXT
F695 83C708 4518 ADD
01.6 I NEXT COOE POINT
F698 4A 451'9 DEC OX
lOOP CONTROL
F699 75EO 4520 JHZ 517
j
DO ALL OF THEM
4521
4522
j--._--
CHAR NOT HATCHED, HIGHT BE IN USER SUPPLIED SECOND HALF
4523
F69B 3eoo
4524 CHP
Al.O AL<> 0 IF ONL'( 1ST HALF SCAHHEO
F690 7412 4525 JE
51. IF
=
0, THEN ALL HAS BEEN SCANNED
F69F 2BCO
4526
SUB AX,AX
F6A1 8E08
452.7 HOV DS,AX ESTABLISH ADDRESSING TO VECTOR
4528 ASSUME
DS:ABSO
F6A3 C43E7COO 4529
LE5 OI,EXT_PTR
j
GET POINTER
F6,6,7 aceD
4530 MOV
AX,ES
; SEE IF THE POINTER REALLY EXISTS
F6A9 OBC7
4531 OR AX,DI ; IF ALL 0, THEN DOESN'T EXIST
F6AB 7404
4532 JZ
51. ; NO SENSE LOOKING
F6AD B080 4533
MOV AL,I,S
I ORIGIN FOR SECOND HALF
F6AF EBD2
4534 JMP 51. ; GO BACK AND TRY FOR IT
4535
ASSUME Ds:OATA
4536
4537
j------
CHARACTER IS FOUND ( AL=O IF NOT FOUND I
F6Bl 4538
S18:
F6Bl 83C408 4539
ADO
SP,8 ; READJUST THE STACK. THROW AWAY SAVE
F664 E910FB 4540 JHP
VIDEO.RETURN
; ALL DONE
4541
GRAPHICS.READ ENDP
4542
;
-------------------------------------------­
4543
EXPAND.MED.COLOR
4544 THIS ROUTINE EXPANDS THE LOW 2 BITS IN BL TO
4545 FILL THE ENTIRE BX REGISTER
4546 ENTRY --
r"-.
4547 BL
=
COLOR TO BE USED ( LOW , BITS )
4548
EXIT - ­
4549 BX
=
COLOR TO BE USED ( 8 REPLICATIONS OF THE 2: COLOR BITS I
4550
;
------------------------------------------- ­
F6B7 4551 51. PROC NEAR
F6B7 80E303
455, Atm BL,3 ; ISOLATE THE COLOR BITS
F6BA 8AC3 4553 HOV
Al,Bl ; COPY TO AL
F6BC 51
4554 PUSH CX ; SAVE REGISTER
F6BD B90300 4555 MOV CX,3 ; NUMBER OF TIMES TO DO THIS
F6CO 4556 S20:
f6CO ODED
4557 SAL AL,l
F6C2 DOEO 4558 SAL AL,I
; lEFT SHIFT BY 2
F6C4 OAD8 4559 OR Bl.Al
; ANOTHER COLOR VERSION INTO 8L
F6C6 E,F8 4560 lOOP
52. ; FILL ALL OF BL
F6C8 8AFB 4561
MOV BH,Bl ; FI LL UPPER PORTION
F6CA 59 4562 POP CX
; REGISTER BACK
F6CB C3 4563 RET ; ALL DONE
4564
51. Etmp
4565
1-------------------------------------------­
4566 EXPAND.BHE
4567 THIS ROUTII1E TAKES THE BYTE IN AL AND DOUBLES ALL
4568
OF THE BITS, TURNING THE 8 BITS INTO 16 BITS.
4569
THE RESULT IS lEFT IN AX
4570
;
-------------------------------------------­
F6CC
4571
521
PRoe
NEAR
F6CC 52
4572 PUSH OX ; SAVE REGISTERS
F6CD 51
4573 PUSH CX
F6CE 53
4574 PUSH BX
F6CF BAOOOO
4575 HOV OX,O
J
RESULT REGISTER
F602 B90100 4576 HOV CX,1 ; MASK REGISTER
F605 4577 S,,:
F605 8BD8 4578
MOV
eX,AX ; BASE INTO TEMP
F607 ,309 4579
AND
BX,ex USE MASK TO EXTRACT A BIT
F6D9 OB03
4580 OR DX,ex PUT INTO RESULT REGISTER
F6DS OlEO 4581
5HL
AX,l
F60D D1E1
4582 SHL
ex,!
SHIFT 6ASE AND MASK BY 1
F6DF 8608 4583 MOV eX.AX ; BASE TO TEMP
F6E1 ,309 4584 AND BX,ex EXTRACT THE SAME BIT
F6El OB03
4585 OR
DX,BX
; PUT INTO RESULT
A-62