prog8/compiler/res/prog8lib/atari/syslib.p8
Irmen de Jong a735939d1e removed confusing GPL software license reference and copyright header from library files. (because of exclusion in output files)
Reworded software license and exclusion clause somewhat again in attempt to make it even clearer.
2022-05-30 20:12:20 +02:00

317 lines
7.4 KiB
Lua

; Prog8 definitions for the Atari800XL
; Including memory registers, I/O registers, Basic and Kernal subroutines.
atari {
&uword NMI_VEC = $FFFA ; 6502 nmi vector, determined by the kernal if banked in
&uword RESET_VEC = $FFFC ; 6502 reset vector, determined by the kernal if banked in
&uword IRQ_VEC = $FFFE ; 6502 interrupt vector, determined by the kernal if banked in
; ---- kernal routines ----
; TODO
asmsub init_system() {
; Initializes the machine to a sane starting state.
; Called automatically by the loader program logic.
; TODO
%asm {{
sei
cld
clc
; TODO reset screen mode etc etc
clv
cli
rts
}}
}
asmsub init_system_phase2() {
%asm {{
rts ; no phase 2 steps on the Atari
}}
}
}
sys {
; ------- lowlevel system routines --------
const ubyte target = 8 ; compilation target specifier. 64 = C64, 128 = C128, 16 = CommanderX16, 8 = atari800XL
asmsub reset_system() {
; Soft-reset the system back to initial power-on Basic prompt.
; TODO
%asm {{
sei
jmp (atari.RESET_VEC)
}}
}
sub wait(uword jiffies) {
; --- wait approximately the given number of jiffies (1/60th seconds)
; TODO
}
asmsub waitvsync() clobbers(A) {
; --- busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
; TODO
%asm {{
nop
rts
}}
}
asmsub internal_stringcopy(uword source @R0, uword target @AY) clobbers (A,Y) {
; Called when the compiler wants to assign a string value to another string.
%asm {{
sta P8ZP_SCRATCH_W1
sty P8ZP_SCRATCH_W1+1
lda cx16.r0
ldy cx16.r0+1
jmp prog8_lib.strcpy
}}
}
asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {
; note: only works for NON-OVERLAPPING memory regions!
; note: can't be inlined because is called from asm as well
%asm {{
ldx cx16.r0
stx P8ZP_SCRATCH_W1 ; source in ZP
ldx cx16.r0+1
stx P8ZP_SCRATCH_W1+1
ldx cx16.r1
stx P8ZP_SCRATCH_W2 ; target in ZP
ldx cx16.r1+1
stx P8ZP_SCRATCH_W2+1
cpy #0
bne _longcopy
; copy <= 255 bytes
tay
bne _copyshort
rts ; nothing to copy
_copyshort
; decrease source and target pointers so we can simply index by Y
lda P8ZP_SCRATCH_W1
bne +
dec P8ZP_SCRATCH_W1+1
+ dec P8ZP_SCRATCH_W1
lda P8ZP_SCRATCH_W2
bne +
dec P8ZP_SCRATCH_W2+1
+ dec P8ZP_SCRATCH_W2
- lda (P8ZP_SCRATCH_W1),y
sta (P8ZP_SCRATCH_W2),y
dey
bne -
rts
_longcopy
sta P8ZP_SCRATCH_B1 ; lsb(count) = remainder in last page
tya
tax ; x = num pages (1+)
ldy #0
- lda (P8ZP_SCRATCH_W1),y
sta (P8ZP_SCRATCH_W2),y
iny
bne -
inc P8ZP_SCRATCH_W1+1
inc P8ZP_SCRATCH_W2+1
dex
bne -
ldy P8ZP_SCRATCH_B1
bne _copyshort
rts
}}
}
asmsub memset(uword mem @R0, uword numbytes @R1, ubyte value @A) clobbers(A,X,Y) {
%asm {{
ldy cx16.r0
sty P8ZP_SCRATCH_W1
ldy cx16.r0+1
sty P8ZP_SCRATCH_W1+1
ldx cx16.r1
ldy cx16.r1+1
jmp prog8_lib.memset
}}
}
asmsub memsetw(uword mem @R0, uword numwords @R1, uword value @AY) clobbers(A,X,Y) {
%asm {{
ldx cx16.r0
stx P8ZP_SCRATCH_W1
ldx cx16.r0+1
stx P8ZP_SCRATCH_W1+1
ldx cx16.r1
stx P8ZP_SCRATCH_W2
ldx cx16.r1+1
stx P8ZP_SCRATCH_W2+1
jmp prog8_lib.memsetw
}}
}
inline asmsub read_flags() -> ubyte @A {
%asm {{
php
pla
}}
}
inline asmsub clear_carry() {
%asm {{
clc
}}
}
inline asmsub set_carry() {
%asm {{
sec
}}
}
inline asmsub clear_irqd() {
%asm {{
cli
}}
}
inline asmsub set_irqd() {
%asm {{
sei
}}
}
inline asmsub exit(ubyte returnvalue @A) {
; -- immediately exit the program with a return code in the A register
; TODO
%asm {{
ldx prog8_lib.orig_stackpointer
txs
rts ; return to original caller
}}
}
inline asmsub progend() -> uword @AY {
%asm {{
lda #<prog8_program_end
ldy #>prog8_program_end
}}
}
}
cx16 {
; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
; they are simulated on the Atari as well but their location in memory is different
; TODO
&uword r0 = $1b00
&uword r1 = $1b02
&uword r2 = $1b04
&uword r3 = $1b06
&uword r4 = $1b08
&uword r5 = $1b0a
&uword r6 = $1b0c
&uword r7 = $1b0e
&uword r8 = $1b10
&uword r9 = $1b12
&uword r10 = $1b14
&uword r11 = $1b16
&uword r12 = $1b18
&uword r13 = $1b1a
&uword r14 = $1b1c
&uword r15 = $1b1e
&word r0s = $1b00
&word r1s = $1b02
&word r2s = $1b04
&word r3s = $1b06
&word r4s = $1b08
&word r5s = $1b0a
&word r6s = $1b0c
&word r7s = $1b0e
&word r8s = $1b10
&word r9s = $1b12
&word r10s = $1b14
&word r11s = $1b16
&word r12s = $1b18
&word r13s = $1b1a
&word r14s = $1b1c
&word r15s = $1b1e
&ubyte r0L = $1b00
&ubyte r1L = $1b02
&ubyte r2L = $1b04
&ubyte r3L = $1b06
&ubyte r4L = $1b08
&ubyte r5L = $1b0a
&ubyte r6L = $1b0c
&ubyte r7L = $1b0e
&ubyte r8L = $1b10
&ubyte r9L = $1b12
&ubyte r10L = $1b14
&ubyte r11L = $1b16
&ubyte r12L = $1b18
&ubyte r13L = $1b1a
&ubyte r14L = $1b1c
&ubyte r15L = $1b1e
&ubyte r0H = $1b01
&ubyte r1H = $1b03
&ubyte r2H = $1b05
&ubyte r3H = $1b07
&ubyte r4H = $1b09
&ubyte r5H = $1b0b
&ubyte r6H = $1b0d
&ubyte r7H = $1b0f
&ubyte r8H = $1b11
&ubyte r9H = $1b13
&ubyte r10H = $1b15
&ubyte r11H = $1b17
&ubyte r12H = $1b19
&ubyte r13H = $1b1b
&ubyte r14H = $1b1d
&ubyte r15H = $1b1f
&byte r0sL = $1b00
&byte r1sL = $1b02
&byte r2sL = $1b04
&byte r3sL = $1b06
&byte r4sL = $1b08
&byte r5sL = $1b0a
&byte r6sL = $1b0c
&byte r7sL = $1b0e
&byte r8sL = $1b10
&byte r9sL = $1b12
&byte r10sL = $1b14
&byte r11sL = $1b16
&byte r12sL = $1b18
&byte r13sL = $1b1a
&byte r14sL = $1b1c
&byte r15sL = $1b1e
&byte r0sH = $1b01
&byte r1sH = $1b03
&byte r2sH = $1b05
&byte r3sH = $1b07
&byte r4sH = $1b09
&byte r5sH = $1b0b
&byte r6sH = $1b0d
&byte r7sH = $1b0f
&byte r8sH = $1b11
&byte r9sH = $1b13
&byte r10sH = $1b15
&byte r11sH = $1b17
&byte r12sH = $1b19
&byte r13sH = $1b1b
&byte r14sH = $1b1d
&byte r15sH = $1b1f
}