mirror of
https://github.com/nathanriggs/AppleIIAsm-Collection.git
synced 2024-12-03 18:49:28 +00:00
239 lines
5.2 KiB
Plaintext
239 lines
5.2 KiB
Plaintext
*
|
|
*``````````````````````````````*
|
|
* DIM82 : INIT 2D ARRAY *
|
|
*- -*
|
|
* THIS SIMPLY CREATES A 1D *
|
|
* ARRAY WITH THE DIM OF *
|
|
* [:AXSIZE] BY [:AYSIZE]. *
|
|
*- -*
|
|
* FIRST BYTE OF MEMORY USED *
|
|
* HOLDS LENGTH OF X (ROWS); *
|
|
* SECOND BYTE HOLDS LENGTH OF *
|
|
* Y (COLUMNS); THIRD BYTE *
|
|
* HOLDS LENGTH OF EACH ELEMENT *
|
|
*- -*
|
|
* CLOBBERS: *
|
|
* *
|
|
* FLAGS: ????---- REG: AXYM *
|
|
*- -*
|
|
* CYCLES: ??? *
|
|
* SIZE: *
|
|
*- -*
|
|
* USAGE: *
|
|
* *
|
|
* LDA #>$300 ; ARRAY ADDR *
|
|
* PHA *
|
|
* LDA #<$300 *
|
|
* PHA *
|
|
* LDA #4 ; X DIMENSION BOUND *
|
|
* PHA *
|
|
* LDA #4 ; Y DIMENSION BOUND *
|
|
* PHA *
|
|
* LDA #1 ; ELEMENT BYTESIZE *
|
|
* PHA *
|
|
* JSR DIM82 *
|
|
*- -*
|
|
* ENTRY *
|
|
* *
|
|
* TOP OF STACK *
|
|
* *
|
|
* LOW BYTE OF RETURN ADDRESS *
|
|
* HI BYTE OF RETURN ADDRESS *
|
|
* ELEMENT SIZE IN BYTES *
|
|
* Y DIMENSION BOUNDARY *
|
|
* X DIMENSION BOUNDARY *
|
|
* ARRAY ADDRESS, LOW BYTE *
|
|
* ARRAY ADDRESS, HIGH BYTE *
|
|
*- -*
|
|
* EXIT *
|
|
* *
|
|
* TOP OF STACK *
|
|
* *
|
|
* LOW BYTE OF RETURN ADDRESS *
|
|
* HI BYTE OF RETURN ADDRESS *
|
|
* *
|
|
* .Y = ARRAY ADDRESS LO BYTE *
|
|
* .X = ARRAY ADDRESS HI BYTE *
|
|
* .A = ELEMENT SIZE *
|
|
* *
|
|
* [RETURN] = TOTAL BYTE SIZE *
|
|
* OF ARRAY. *
|
|
* *
|
|
* [RETLEN] = LENGTH IN BYTES *
|
|
* OF THE RETURN VALUE. *
|
|
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
|
|
*
|
|
DIM82
|
|
*
|
|
** SAVE RETURN ADDRESS
|
|
*
|
|
PLA
|
|
STA RETADR
|
|
PLA
|
|
STA RETADR+1
|
|
*
|
|
** GET PARAMETERS
|
|
*
|
|
PLA
|
|
STA :MCAND ; ELEMENT LENGTH
|
|
PLA
|
|
STA :AYSIZE
|
|
STA :AYBAK
|
|
PLA
|
|
STA :AXSIZE
|
|
STA :AXBAK
|
|
PLA
|
|
STA ADDR1
|
|
PLA
|
|
STA ADDR1+1
|
|
LDA #0
|
|
STA :MCAND+1
|
|
*
|
|
** LOOP THROUGH Y, CLEARING MEMORY
|
|
** FOR X BYTES TIMES ELEMENT SIZE,
|
|
** MOVING TO END OF LAST CLEAR
|
|
** UNTIL FINISHED
|
|
*
|
|
** MULTIPLY X AND Y
|
|
*
|
|
LDA #0
|
|
TAY
|
|
STY SCRATCH
|
|
BEQ :ENTLP
|
|
*
|
|
:DOADD
|
|
CLC
|
|
ADC :AXSIZE
|
|
TAX
|
|
*
|
|
TYA
|
|
ADC SCRATCH
|
|
TAY
|
|
TXA
|
|
*
|
|
:LP
|
|
ASL :AXSIZE
|
|
ROL SCRATCH
|
|
:ENTLP
|
|
LSR :AYSIZE
|
|
BCS :DOADD
|
|
BNE :LP
|
|
*
|
|
STX :MLIER
|
|
STY :MLIER+1
|
|
*
|
|
** NOW MULTIPLY BY LENGTH OF ELEMENTS
|
|
*
|
|
LDA #0
|
|
STA :PROD
|
|
STA :PROD+1
|
|
STA :PROD+2
|
|
STA :PROD+3
|
|
LDX #$10
|
|
:SHIFTR LSR :MLIER+1
|
|
ROR :MLIER
|
|
BCC :ROTR
|
|
LDA :PROD+2
|
|
CLC
|
|
ADC :MCAND
|
|
STA :PROD+2
|
|
LDA :PROD+3
|
|
ADC :MCAND+1
|
|
:ROTR
|
|
ROR
|
|
STA :PROD+3
|
|
ROR :PROD+2
|
|
ROR :PROD+1
|
|
ROR :PROD
|
|
DEX
|
|
BNE :SHIFTR
|
|
*
|
|
CLC
|
|
INC :PROD ; INCREASE BY 3
|
|
INC :PROD
|
|
INC :PROD
|
|
BCC :NOCAR
|
|
INC :PROD+1
|
|
:NOCAR
|
|
*
|
|
** NOW CLEAR MEMORY BLOCKS, WHOLE PAGES FIRST
|
|
*
|
|
LDA #$00 ; FILL VALUE
|
|
LDX :PROD+1 ; NOTE THAT THIS WON'T
|
|
; GO BEYOND A 16BIT VALUE;
|
|
; ANYTHING HIGHER THAN
|
|
; 16BITS IS MORE THAN
|
|
; THERE IS MEMORY IN A
|
|
; STANDARD APPLE ][
|
|
BEQ :PART
|
|
LDY #0
|
|
:FULL
|
|
STA (ADDR1),Y
|
|
INY
|
|
BNE :FULL
|
|
INC ADDR1+1
|
|
DEX
|
|
BNE :FULL ; LOOP UNTIL PAGES DONE
|
|
*
|
|
** NOW DO REMAINING BYTES
|
|
*
|
|
:PART
|
|
LDX :PROD
|
|
BEQ :MFEXIT
|
|
LDY #0
|
|
:PARTLP
|
|
STA (ADDR1),Y
|
|
INY
|
|
DEX
|
|
BNE :PARTLP ; LOOP UNTIL DONE
|
|
:MFEXIT
|
|
*
|
|
** NOW SET SIZES
|
|
*
|
|
LDY #0
|
|
LDA :AXBAK
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA :AYBAK
|
|
STA (ADDR1),Y
|
|
INY
|
|
LDA :MCAND
|
|
STA (ADDR1),Y
|
|
*
|
|
** RESTORE RETURN ADDRESS
|
|
*
|
|
LDA RETADR+1
|
|
PHA
|
|
LDA RETADR
|
|
PHA
|
|
*
|
|
** RETURN POINTER TO STARTING ADDRESS OF ARRAY
|
|
** AND STORE TOTAL BYTE SIZE IN RETURN MEM
|
|
*
|
|
LDY ADDR1
|
|
LDX ADDR1+1
|
|
LDA :PROD
|
|
STA RETURN
|
|
LDA :PROD+1
|
|
STA RETURN+1
|
|
LDA :PROD+2
|
|
STA RETURN+2
|
|
LDA :PROD+3
|
|
STA RETURN+3
|
|
LDA #4 ; SIZE OF RETURN
|
|
STA RETLEN
|
|
LDA :MCAND
|
|
*
|
|
RTS
|
|
*
|
|
** DATA
|
|
*
|
|
:PROD DS 4
|
|
:AXSIZE DS 1
|
|
:AYSIZE DS 1
|
|
:AXBAK DS 1
|
|
:AYBAK DS 1
|
|
:MLIER DS 2
|
|
:MCAND DS 2
|
|
*
|