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C02/x16/include/abiregs.a02
2019-12-21 13:52:34 -05:00

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;Commander X16 ABI Registers Assembly Language Routines
;Zero Page System Variables - x16emu Release 34 Memory Map
ABIPTR EQU $00 ;Pointer for ABI Functions
R0 EQU $02 ;ABI Register 0
R0L EQU $02 ;ABI Register 0 LSB
R0H EQU $03 ;ABI Register 0 MSB
R1 EQU $04 ;ABI Register 1
R1L EQU $04 ;ABI Register 1 LSB
R1H EQU $05 ;ABI Register 1 MSB
R2 EQU $06 ;ABI Register 2
R2L EQU $06 ;ABI Register 2 LSB
R2H EQU $07 ;ABI Register 2 MSB
R3 EQU $08 ;ABI Register 3
R3L EQU $08 ;ABI Register 3 LSB
R3H EQU $09 ;ABI Register 3 MSB
R4 EQU $0A ;ABI Register 4
R4L EQU $0A ;ABI Register 4 LSB
R4H EQU $0B ;ABI Register 4 MSB
R5 EQU $0C ;ABI Register 5
R5L EQU $0C ;ABI Register 5 LSB
R5H EQU $0D ;ABI Register 5 MSB
R6 EQU $0E ;ABI Register 6
R6L EQU $0E ;ABI Register 6 LSB
R6H EQU $0F ;ABI Register 6 MSB
R7 EQU $10 ;ABI Register 7
R7L EQU $10 ;ABI Register 7 LSB
R7H EQU $11 ;ABI Register 7 MSB
R8 EQU $12 ;ABI Register 8
R8L EQU $12 ;ABI Register 8 LSB
R8H EQU $13 ;ABI Register 8 MSB
R9 EQU $14 ;ABI Register 9
R9L EQU $14 ;ABI Register 9 LSB
R9H EQU $15 ;ABI Register 9 MSB
R10 EQU $16 ;ABI Register 10
R10L EQU $16 ;ABI Register 10 LSB
R10H EQU $17 ;ABI Register 10 MSB
R11 EQU $18 ;ABI Register 11
R11L EQU $18 ;ABI Register 11 LSB
R11H EQU $19 ;ABI Register 11 MSB
R12 EQU $1A ;ABI Register 12
R12L EQU $1A ;ABI Register 12 LSB
R12H EQU $1B ;ABI Register 12 MSB
R13 EQU $1C ;ABI Register 13
R13L EQU $1C ;ABI Register 13 LSB
R13H EQU $1D ;ABI Register 13 MSB
R14 EQU $1E ;ABI Register 14
R14L EQU $1E ;ABI Register 14 LSB
R14H EQU $1F ;ABI Register 14 MSB
R15 EQU $20 ;ABI Register 15
R15L EQU $20 ;ABI Register 15 LSB
R15H EQU $21 ;ABI Register 15 MSB
;Read ABI Registers into Array or Struct
GETABI: STX ABIPTR ;Store Array Address
STY ABIPTR+1
TAY ;Copy Array Size into Y Register
GETABY: DEY ;Decrement Counter
BMI .GETABX ;If Not Negative
LDA R0,Y ;Get Byte from ABI Register
STA (ABIPTR),Y ;And write to ABI Register
BRA GETABY ;and Loop
.GETABX RTS
;Return ABI Register Contents
GETABR: TAX ;Copy Register
;Write Array or Struct to ABI Registers
SETABI: STX ABIPTR ;Store Array Address
STY ABIPTR+1
TAY ;Copy Array Size into Y Register
SETABY: DEY ;Decrement Counter
BMI .SETABX ;If Not Negative
LDA (ABIPTR),Y ;Get Byte from Array or Struct
STA R0,Y ;Store in ABI Register
BRA SETABY ;and Loop
.SETABX RTS