george-emu/roms/macro.inc

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.macro breakpoint ; $02 isn't a valid instruction, the emulator will see this and halt, dump memory contents
.byte $02
.endm
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.macro pop ; drops a data stack cell
inx
inx
.endm
.macro pop2 ; drops 2 data stack cells
inx
inx
inx
inx
.endm
.macro push ; push a data stack cell
dex
dex
.endm
.macro push2 ; push 2 data stack cells
dex
dex
dex
dex
.endm
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.macro push_char, char; pushes an ascii character code onto the stack
lda \char
push
sta 0, x ; char low byte
stz 1, x ; char high byte
.endm
.macro push_coords, coord_x, coord_y ; push a set of (x,y) coordinates onto the data stack
lda \coord_x
push
sta 0, x ; low byte
stz 1,x ; high byte is zero
lda \coord_y
push
sta 0,x ; same here
stz 1,x
.endm
.macro to_r ; pop the top of the stack off and save it in the return (hardware) stack: (n -- )
lda 1, x
pha
lda 0, x
pha
pop
.endm
.macro from_r ; pop the top of the return stack off and put it on the data stack: ( -- n)
push
pla
sta 0, x
pla
sta 1, x
.endm