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CL I
TURN OFF INTERRUPTS
MOV
BX ,(lBUFFER TAl L
GET THE END PO I NTER TO THE BUFFER
MOV
S I, BX
-
SAVE THE VALUE
CALL
K4
ADVANCE THE TA I L
CMP
BX, (lBUFFER HEAD
HAS THE BUFFER WRAPPED AROUND
JE
K62
-
BUFFER FULL BEEP
MOV
[S I ] ,AX
STORE THE VALUE
MOV
(lBUFFER TAl L ,BX
MOVE THE PO I NTER UP
MOV
AL ,EO I -
END OF I NTERRUPT COMMAND
OUT
020H,AL
;
SEND COMMAND TO INTERRUPT CONTROL PORT
MOV
AX, 091 02H
; MOVE I N POST CODE
&
TYPE
I NT
15H
; PERFORM OTHER FUNCT I ON
AND
(lKB FLAG 3,NOT LC EO+LC El
; RESET LAST CHAR H.C. FLAG
JMP
K27-
-
-
-
INTERRUPT_RETURN
; - - - - - - BUFFER
I S FULL SOUND THE BEEPER
IBM Personal Computer MACRO Assembler
Version 2.00
KEYBRD - - -
0 I /10/86
KEYBOARD ADAPTER BIOS
ENABLE I NTERRUPT CONTROLLER CH I P
DIVISOR FOR 1760 HZ
SHORT BEEP COUNT (1/16 +
1/64 DELAY)
GO TO COMMON BEEP HANDLER
EXIT
5-55
BUFFER-F I LL
I S TH I S AN I GNORE CHAR
YES, DO NOTHING WITH IT
LOOK FOR - I PSEUDO SCAN
NEAR_I NTERRUPT_RETURN
NEAR- I NTERRUPT"'RETURN
I NTERRUPT_RETURN
1-10
01-10-86
KEYBOARD (01/10/86)
AL,EOI
I NTAOO, AL
CX,678
BL,4
BEEP
K27
K26
AL,-I
K59
AH,-1
K61
MOV
OUT
MOV
MOV
CALL
JMP
JMP
CMP
JE
CMP
JNE
KB_INT_I
ENDP
K62:
K61 :
K59:
K57:
882
883
0500
884
0500 3C FF
885
050F 74 05
886
051 1 80 FC FF
887
0514 75 03
888
889
0516
890
0516 E9 02CA R
891
892
0519
893
0519 FA
894
051A 8B
IE OOIC R
895
051E 8B F3
896
0520 E8 01 14 R
897
0523 3B IE 001A R
898
0527 74 17
899
0529 89 04
900
052B 89
IE 00 I C R
90 I
052F BO 20
902
0531
E6 20
903
0533 B8 9102
904
0536 CD 15
905
0538 80 26 0096 R FC
906
0530 E9 0204 R
907
908
909
9100540
911
0540 BO 20
912
0542 E6 20
913
0544 B9 02A6
914
0547 B3 04
915
0549 E8 0000 E
916
054C E9 0204 R
917
918
054F
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- Section 1. System Board
- 64/256K System Board
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