LISTING3.TXT
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* *
* 68000 ASSEMBLY COURSE ON ATARI ST *
* *
* by The Fierce Rabbit (from 44E) *
* *
* Second series *
* *
* Listing number 3 *
* *
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INCLUDE "B:\START.S"
MOVE.L #MESSAGE,-(SP) introductory message
MOVE.W #9,-(SP)
TRAP #1
ADDQ.L #6,SP
TOUCHE MOVE.W #7,-(SP) waiting for a keypress
TRAP #1
ADDQ.L #2,SP
SWAP D0 to get the scan code
CMP.W #1,D0 escape?
BEQ FIN yes so bye bye
CMP.W #$3B,D0 comparing to F1
BLO TOUCHE below therefore not valid
CMP.W #$44,D0 comparing to F10
BHI TOUCHE above therefore not valid
* The key is valid
LEA TABLE,A0
SUB.W #$3B,D0 to get a number from 0 to 9
* MULU.W #2,D0 ATTENTION! why the star beginning??
MOVE.W 0(A0,D0.W),D1
MOVE.W D1,-(SP)
MOVE.W #2,-(SP)
TRAP #1
ADDQ.L #6,SP
BRA TOUCHE
FIN CLR.W -(SP)
TRAP #1
*--------------------------------------------------*
SECTION DATA
MESSAGE DC.B 27,"E","PRESS A FUNCTION KEY",13,10
DC.B "ESCAPE TO EXIT",13,10,0
EVEN
TABLE DC.W "A","Z","E","R","T","Y","U","I","O","P"
SECTION BSS
DS.L 256
STACK DS.L 1
END
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