prog8/compiler/res/prog8lib/c64/syslib.p8
2024-01-18 22:31:34 +01:00

947 lines
32 KiB
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; Prog8 definitions for the Commodore-64
; Including memory registers, I/O registers, Basic and Kernal subroutines.
%option no_symbol_prefixing, ignore_unused
cbm {
; Commodore (CBM) common variables, vectors and kernal routines
&ubyte TIME_HI = $a0 ; software jiffy clock, hi byte
&ubyte TIME_MID = $a1 ; .. mid byte
&ubyte TIME_LO = $a2 ; .. lo byte. Updated by IRQ every 1/60 sec
&ubyte STATUS = $90 ; kernal status variable for I/O
&ubyte STKEY = $91 ; various keyboard statuses (updated by IRQ)
&ubyte SFDX = $cb ; current key pressed (matrix value) (updated by IRQ)
&ubyte SHFLAG = $028d ; various modifier key status (updated by IRQ)
&ubyte COLOR = $0286 ; cursor color
&ubyte HIBASE = $0288 ; screen base address / 256 (hi-byte of screen memory address)
&uword IERROR = $0300
&uword IMAIN = $0302
&uword ICRNCH = $0304
&uword IQPLOP = $0306
&uword IGONE = $0308
&uword IEVAL = $030a
&ubyte SAREG = $030c ; register storage for A for SYS calls
&ubyte SXREG = $030d ; register storage for X for SYS calls
&ubyte SYREG = $030e ; register storage for Y for SYS calls
&ubyte SPREG = $030f ; register storage for P (status register) for SYS calls
&uword USRADD = $0311 ; vector for the USR() basic command
; $0313 is unused.
&uword CINV = $0314 ; IRQ vector (in ram)
&uword CBINV = $0316 ; BRK vector (in ram)
&uword NMINV = $0318 ; NMI vector (in ram)
&uword IOPEN = $031a
&uword ICLOSE = $031c
&uword ICHKIN = $031e
&uword ICKOUT = $0320
&uword ICLRCH = $0322
&uword IBASIN = $0324
&uword IBSOUT = $0326
&uword ISTOP = $0328
&uword IGETIN = $032a
&uword ICLALL = $032c
&uword USERCMD = $032e
&uword ILOAD = $0330
&uword ISAVE = $0332
&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
; the default addresses for the character screen chars and colors
const uword Screen = $0400 ; to have this as an array[40*25] the compiler would have to support array size > 255
const uword Colors = $d800 ; to have this as an array[40*25] the compiler would have to support array size > 255
; ---- CBM ROM kernal routines (C64 addresses) ----
romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y) ; print null-terminated string (use txt.print instead)
romsub $E544 = CLEARSCR() clobbers(A,X,Y) ; clear the screen
romsub $E566 = HOMECRSR() clobbers(A,X,Y) ; cursor to top left of screen
romsub $EA31 = IRQDFRT() clobbers(A,X,Y) ; default IRQ routine
romsub $EA81 = IRQDFEND() clobbers(A,X,Y) ; default IRQ end/cleanup
romsub $FF81 = CINT() clobbers(A,X,Y) ; (alias: SCINIT) initialize screen editor and video chip
romsub $FF84 = IOINIT() clobbers(A, X) ; initialize I/O devices (CIA, SID, IRQ)
romsub $FF87 = RAMTAS() clobbers(A,X,Y) ; initialize RAM, tape buffer, screen
romsub $FF8A = RESTOR() clobbers(A,X,Y) ; restore default I/O vectors
romsub $FF8D = VECTOR(uword userptr @ XY, bool dir @ Pc) clobbers(A,Y) ; read/set I/O vector table
romsub $FF90 = SETMSG(ubyte value @ A) ; set Kernal message control flag
romsub $FF93 = SECOND(ubyte address @ A) clobbers(A) ; (alias: LSTNSA) send secondary address after LISTEN
romsub $FF96 = TKSA(ubyte address @ A) clobbers(A) ; (alias: TALKSA) send secondary address after TALK
romsub $FF99 = MEMTOP(uword address @ XY, bool dir @ Pc) -> uword @ XY ; read/set top of memory pointer
romsub $FF9C = MEMBOT(uword address @ XY, bool dir @ Pc) -> uword @ XY ; read/set bottom of memory pointer
romsub $FF9F = SCNKEY() clobbers(A,X,Y) ; scan the keyboard
romsub $FFA2 = SETTMO(ubyte timeout @ A) ; set time-out flag for IEEE bus
romsub $FFA5 = ACPTR() -> ubyte @ A ; (alias: IECIN) input byte from serial bus
romsub $FFA8 = CIOUT(ubyte databyte @ A) ; (alias: IECOUT) output byte to serial bus
romsub $FFAB = UNTLK() clobbers(A) ; command serial bus device to UNTALK
romsub $FFAE = UNLSN() clobbers(A) ; command serial bus device to UNLISTEN
romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A) ; command serial bus device to LISTEN
romsub $FFB4 = TALK(ubyte device @ A) clobbers(A) ; command serial bus device to TALK
romsub $FFB7 = READST() -> ubyte @ A ; read I/O status word (use CLEARST to reset it to 0)
romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y) ; set logical file parameters
romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY) ; set filename parameters
romsub $FFC0 = OPEN() clobbers(X,Y) -> bool @Pc, ubyte @A ; (via 794 ($31A)) open a logical file
romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y) ; (via 796 ($31C)) close a logical file
romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> bool @Pc ; (via 798 ($31E)) define an input channel
romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X) ; (via 800 ($320)) define an output channel
romsub $FFCC = CLRCHN() clobbers(A,X) ; (via 802 ($322)) restore default devices
romsub $FFCF = CHRIN() clobbers(X, Y) -> ubyte @ A ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
romsub $FFD2 = CHROUT(ubyte character @ A) ; (via 806 ($326)) output a character
romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> bool @Pc, ubyte @ A, uword @ XY ; (via 816 ($330)) load from device
romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> bool @ Pc, ubyte @ A ; (via 818 ($332)) save to a device
romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y) ; set the software clock
romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y ; read the software clock (A=lo,X=mid,Y=high)
romsub $FFE1 = STOP() clobbers(X) -> bool @ Pz, ubyte @ A ; (via 808 ($328)) check the STOP key (and some others in A)
romsub $FFE4 = GETIN() clobbers(X,Y) -> bool @Pc, ubyte @ A ; (via 810 ($32A)) get a character
romsub $FFE7 = CLALL() clobbers(A,X) ; (via 812 ($32C)) close all files
romsub $FFEA = UDTIM() clobbers(A,X) ; update the software clock
romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y ; read number of screen rows and columns
romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, bool dir @ Pc) -> ubyte @ X, ubyte @ Y ; read/set position of cursor on screen. Use txt.plot for a 'safe' wrapper that preserves X.
romsub $FFF3 = IOBASE() -> uword @ XY ; read base address of I/O devices
asmsub STOP2() clobbers(X) -> ubyte @A {
; -- check if STOP key was pressed, returns true if so. More convenient to use than STOP() because that only sets the carry status flag.
%asm {{
jsr cbm.STOP
beq +
lda #0
rts
+ lda #1
rts
}}
}
asmsub RDTIM16() clobbers(X) -> uword @AY {
; -- like RDTIM() but only returning the lower 16 bits in AY for convenience
%asm {{
jsr cbm.RDTIM
pha
txa
tay
pla
rts
}}
}
sub CLEARST() {
; -- Set the ST status variable back to 0. (there's no direct kernal call for this)
; Note: a drive error state (blinking led) isn't cleared! You can use diskio.status() to clear that.
SETNAM(0, $0000)
SETLFS(15, 3, 15)
void OPEN()
CLOSE(15)
}
}
c64 {
; C64 I/O registers (VIC, SID, CIA)
; the default locations of the 8 sprite pointers (store address of sprite / 64)
; (depending on the VIC bank and screen ram address selection these can be shifted around though,
; see the two routines after this for a dynamic way of determining the correct memory location)
&ubyte SPRPTR0 = 2040
&ubyte SPRPTR1 = 2041
&ubyte SPRPTR2 = 2042
&ubyte SPRPTR3 = 2043
&ubyte SPRPTR4 = 2044
&ubyte SPRPTR5 = 2045
&ubyte SPRPTR6 = 2046
&ubyte SPRPTR7 = 2047
&ubyte[8] SPRPTR = 2040 ; the 8 sprite pointers as an array.
; ---- VIC-II 6567/6569/856x registers ----
&ubyte SP0X = $d000
&ubyte SP0Y = $d001
&ubyte SP1X = $d002
&ubyte SP1Y = $d003
&ubyte SP2X = $d004
&ubyte SP2Y = $d005
&ubyte SP3X = $d006
&ubyte SP3Y = $d007
&ubyte SP4X = $d008
&ubyte SP4Y = $d009
&ubyte SP5X = $d00a
&ubyte SP5Y = $d00b
&ubyte SP6X = $d00c
&ubyte SP6Y = $d00d
&ubyte SP7X = $d00e
&ubyte SP7Y = $d00f
&ubyte[16] SPXY = $d000 ; the 8 sprite X and Y registers as an array.
&uword[8] SPXYW = $d000 ; the 8 sprite X and Y registers as a combined xy word array.
&ubyte MSIGX = $d010
&ubyte SCROLY = $d011
&ubyte RASTER = $d012
&ubyte LPENX = $d013
&ubyte LPENY = $d014
&ubyte SPENA = $d015
&ubyte SCROLX = $d016
&ubyte YXPAND = $d017
&ubyte VMCSB = $d018
&ubyte VICIRQ = $d019
&ubyte IREQMASK = $d01a
&ubyte SPBGPR = $d01b
&ubyte SPMC = $d01c
&ubyte XXPAND = $d01d
&ubyte SPSPCL = $d01e
&ubyte SPBGCL = $d01f
&ubyte EXTCOL = $d020 ; border color
&ubyte BGCOL0 = $d021 ; screen color
&ubyte BGCOL1 = $d022
&ubyte BGCOL2 = $d023
&ubyte BGCOL4 = $d024
&ubyte SPMC0 = $d025
&ubyte SPMC1 = $d026
&ubyte SP0COL = $d027
&ubyte SP1COL = $d028
&ubyte SP2COL = $d029
&ubyte SP3COL = $d02a
&ubyte SP4COL = $d02b
&ubyte SP5COL = $d02c
&ubyte SP6COL = $d02d
&ubyte SP7COL = $d02e
&ubyte[8] SPCOL = $d027
; ---- end of VIC-II registers ----
; ---- CIA 6526 1 & 2 registers ----
&ubyte CIA1PRA = $DC00 ; CIA 1 DRA, keyboard column drive (and joystick control port #2)
&ubyte CIA1PRB = $DC01 ; CIA 1 DRB, keyboard row port (and joystick control port #1)
&ubyte CIA1DDRA = $DC02 ; CIA 1 DDRA, keyboard column
&ubyte CIA1DDRB = $DC03 ; CIA 1 DDRB, keyboard row
&ubyte CIA1TAL = $DC04 ; CIA 1 timer A low byte
&ubyte CIA1TAH = $DC05 ; CIA 1 timer A high byte
&ubyte CIA1TBL = $DC06 ; CIA 1 timer B low byte
&ubyte CIA1TBH = $DC07 ; CIA 1 timer B high byte
&ubyte CIA1TOD10 = $DC08 ; time of day, 1/10 sec.
&ubyte CIA1TODSEC = $DC09 ; time of day, seconds
&ubyte CIA1TODMMIN = $DC0A ; time of day, minutes
&ubyte CIA1TODHR = $DC0B ; time of day, hours
&ubyte CIA1SDR = $DC0C ; Serial Data Register
&ubyte CIA1ICR = $DC0D
&ubyte CIA1CRA = $DC0E
&ubyte CIA1CRB = $DC0F
&ubyte CIA2PRA = $DD00 ; CIA 2 DRA, serial port and video address
&ubyte CIA2PRB = $DD01 ; CIA 2 DRB, RS232 port / USERPORT
&ubyte CIA2DDRA = $DD02 ; CIA 2 DDRA, serial port and video address
&ubyte CIA2DDRB = $DD03 ; CIA 2 DDRB, RS232 port / USERPORT
&ubyte CIA2TAL = $DD04 ; CIA 2 timer A low byte
&ubyte CIA2TAH = $DD05 ; CIA 2 timer A high byte
&ubyte CIA2TBL = $DD06 ; CIA 2 timer B low byte
&ubyte CIA2TBH = $DD07 ; CIA 2 timer B high byte
&ubyte CIA2TOD10 = $DD08 ; time of day, 1/10 sec.
&ubyte CIA2TODSEC = $DD09 ; time of day, seconds
&ubyte CIA2TODMIN = $DD0A ; time of day, minutes
&ubyte CIA2TODHR = $DD0B ; time of day, hours
&ubyte CIA2SDR = $DD0C ; Serial Data Register
&ubyte CIA2ICR = $DD0D
&ubyte CIA2CRA = $DD0E
&ubyte CIA2CRB = $DD0F
; ---- end of CIA registers ----
; ---- SID 6581/8580 registers ----
&ubyte FREQLO1 = $D400 ; channel 1 freq lo
&ubyte FREQHI1 = $D401 ; channel 1 freq hi
&uword FREQ1 = $D400 ; channel 1 freq (word)
&ubyte PWLO1 = $D402 ; channel 1 pulse width lo (7-0)
&ubyte PWHI1 = $D403 ; channel 1 pulse width hi (11-8)
&uword PW1 = $D402 ; channel 1 pulse width (word)
&ubyte CR1 = $D404 ; channel 1 voice control register
&ubyte AD1 = $D405 ; channel 1 attack & decay
&ubyte SR1 = $D406 ; channel 1 sustain & release
&ubyte FREQLO2 = $D407 ; channel 2 freq lo
&ubyte FREQHI2 = $D408 ; channel 2 freq hi
&uword FREQ2 = $D407 ; channel 2 freq (word)
&ubyte PWLO2 = $D409 ; channel 2 pulse width lo (7-0)
&ubyte PWHI2 = $D40A ; channel 2 pulse width hi (11-8)
&uword PW2 = $D409 ; channel 2 pulse width (word)
&ubyte CR2 = $D40B ; channel 2 voice control register
&ubyte AD2 = $D40C ; channel 2 attack & decay
&ubyte SR2 = $D40D ; channel 2 sustain & release
&ubyte FREQLO3 = $D40E ; channel 3 freq lo
&ubyte FREQHI3 = $D40F ; channel 3 freq hi
&uword FREQ3 = $D40E ; channel 3 freq (word)
&ubyte PWLO3 = $D410 ; channel 3 pulse width lo (7-0)
&ubyte PWHI3 = $D411 ; channel 3 pulse width hi (11-8)
&uword PW3 = $D410 ; channel 3 pulse width (word)
&ubyte CR3 = $D412 ; channel 3 voice control register
&ubyte AD3 = $D413 ; channel 3 attack & decay
&ubyte SR3 = $D414 ; channel 3 sustain & release
&ubyte FCLO = $D415 ; filter cutoff lo (2-0)
&ubyte FCHI = $D416 ; filter cutoff hi (10-3)
&uword FC = $D415 ; filter cutoff (word)
&ubyte RESFILT = $D417 ; filter resonance and routing
&ubyte MVOL = $D418 ; filter mode and main volume control
&ubyte POTX = $D419 ; potentiometer X
&ubyte POTY = $D41A ; potentiometer Y
&ubyte OSC3 = $D41B ; channel 3 oscillator value read
&ubyte ENV3 = $D41C ; channel 3 envelope value read
; ---- end of SID registers ----
sub get_vic_memory_base() -> uword {
; one of the 4 possible banks. $0000/$4000/$8000/$c000.
c64.CIA2DDRA |= %11
return ((c64.CIA2PRA & 3) ^ 3) as uword << 14
}
sub get_char_matrix_ptr() -> uword {
; Usually the character screen matrix is at 1024-2039 (see above)
; However the vic memory configuration can be altered and this moves these registers with it.
; So this routine determines it dynamically from the VIC memory setup.
uword chars_matrix_offset = (c64.VMCSB & $f0) as uword << 6
return get_vic_memory_base() + chars_matrix_offset
}
sub get_bitmap_ptr() -> uword {
return get_vic_memory_base() + ((c64.VMCSB & %00001000) as uword << 10)
}
sub get_sprite_addr_ptrs() -> uword {
; Usually the sprite address pointers are at addresses 2040-2047 (see above)
; However the vic memory configuration can be altered and this moves these registers with it.
; So this routine determines it dynamically from the VIC memory setup.
return get_char_matrix_ptr() + 1016
}
sub set_sprite_ptr(ubyte sprite_num, uword sprite_data_address) {
; Sets the sprite data pointer to the given address.
; Because it takes some time to calculate things based on the vic memory setup,
; its only suitable if you're not continuously changing the data address.
; Otherwise store the correct sprite data pointer location somewhere yourself and reuse it.
@(get_sprite_addr_ptrs() + sprite_num) = lsb(sprite_data_address / 64)
}
}
sys {
; ------- lowlevel system routines --------
const ubyte target = 64 ; compilation target specifier. 64 = C64, 128 = C128, 16 = CommanderX16.
asmsub init_system() {
; Initializes the machine to a sane starting state.
; Called automatically by the loader program logic.
; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
; Also a different color scheme is chosen to identify ourselves a little.
; Uppercase charset is activated.
%asm {{
sei
cld
lda #%00101111
sta $00
lda #%00100111
sta $01
jsr cbm.IOINIT
jsr cbm.RESTOR
jsr cbm.CINT
lda #6
sta c64.EXTCOL
lda #7
sta cbm.COLOR
lda #0
sta c64.BGCOL0
jsr disable_runstop_and_charsetswitch
clc
clv
cli
rts
}}
}
asmsub init_system_phase2() {
%asm {{
rts ; no phase 2 steps on the C64
}}
}
asmsub cleanup_at_exit() {
; executed when the main subroutine does rts
%asm {{
lda #31
sta $01 ; bank the kernal in
jsr cbm.CLRCHN ; reset i/o channels
jsr enable_runstop_and_charsetswitch
_exitcode = *+1
lda #0 ; exit code possibly modified in exit()
rts
}}
}
asmsub disable_runstop_and_charsetswitch() clobbers(A) {
%asm {{
lda #$80
sta 657 ; disable charset switching
lda #239
sta 808 ; disable run/stop key
rts
}}
}
asmsub enable_runstop_and_charsetswitch() clobbers(A) {
%asm {{
lda #0
sta 657 ; enable charset switching
lda #237
sta 808 ; enable run/stop key
rts
}}
}
asmsub save_prog8_internals() {
%asm {{
lda P8ZP_SCRATCH_B1
sta save_SCRATCH_ZPB1
lda P8ZP_SCRATCH_REG
sta save_SCRATCH_ZPREG
lda P8ZP_SCRATCH_W1
sta save_SCRATCH_ZPWORD1
lda P8ZP_SCRATCH_W1+1
sta save_SCRATCH_ZPWORD1+1
lda P8ZP_SCRATCH_W2
sta save_SCRATCH_ZPWORD2
lda P8ZP_SCRATCH_W2+1
sta save_SCRATCH_ZPWORD2+1
rts
save_SCRATCH_ZPB1 .byte 0
save_SCRATCH_ZPREG .byte 0
save_SCRATCH_ZPWORD1 .word 0
save_SCRATCH_ZPWORD2 .word 0
}}
}
asmsub restore_prog8_internals() {
%asm {{
lda save_prog8_internals.save_SCRATCH_ZPB1
sta P8ZP_SCRATCH_B1
lda save_prog8_internals.save_SCRATCH_ZPREG
sta P8ZP_SCRATCH_REG
lda save_prog8_internals.save_SCRATCH_ZPWORD1
sta P8ZP_SCRATCH_W1
lda save_prog8_internals.save_SCRATCH_ZPWORD1+1
sta P8ZP_SCRATCH_W1+1
lda save_prog8_internals.save_SCRATCH_ZPWORD2
sta P8ZP_SCRATCH_W2
lda save_prog8_internals.save_SCRATCH_ZPWORD2+1
sta P8ZP_SCRATCH_W2+1
rts
}}
}
asmsub set_irq(uword handler @AY) clobbers(A) {
%asm {{
sei
sta _modified+1
sty _modified+2
lda #<_irq_handler
sta cbm.CINV
lda #>_irq_handler
sta cbm.CINV+1
cli
rts
_irq_handler
jsr sys.save_prog8_internals
cld
_modified
jsr $ffff ; modified
pha
jsr sys.restore_prog8_internals
pla
beq +
jmp cbm.IRQDFRT ; continue with normal kernal irq routine
+ lda #$ff
sta c64.VICIRQ ; acknowledge raster irq
lda c64.CIA1ICR ; acknowledge CIA1 interrupt
pla
tay
pla
tax
pla
rti
}}
}
asmsub restore_irq() clobbers(A) {
%asm {{
sei
lda #<cbm.IRQDFRT
sta cbm.CINV
lda #>cbm.IRQDFRT
sta cbm.CINV+1
lda #0
sta c64.IREQMASK ; disable raster irq
lda #%10000001
sta c64.CIA1ICR ; restore CIA1 irq
cli
rts
}}
}
asmsub set_rasterirq(uword handler @AY, uword rasterpos @R0) clobbers(A) {
%asm {{
sei
sta _modified+1
sty _modified+2
lda cx16.r0
ldy cx16.r0+1
jsr _setup_raster_irq
lda #<_raster_irq_handler
sta cbm.CINV
lda #>_raster_irq_handler
sta cbm.CINV+1
cli
rts
_raster_irq_handler
jsr sys.save_prog8_internals
cld
_modified
jsr $ffff ; modified
pha
jsr sys.restore_prog8_internals
lda #$ff
sta c64.VICIRQ ; acknowledge raster irq
pla
beq +
jmp cbm.IRQDFRT ; continue with kernal irq routine
+ pla
tay
pla
tax
pla
rti
_setup_raster_irq
pha
lda #%01111111
sta c64.CIA1ICR ; "switch off" interrupts signals from cia-1
sta c64.CIA2ICR ; "switch off" interrupts signals from cia-2
and c64.SCROLY
sta c64.SCROLY ; clear most significant bit of raster position
lda c64.CIA1ICR ; ack previous irq
lda c64.CIA2ICR ; ack previous irq
pla
sta c64.RASTER ; set the raster line number where interrupt should occur
cpy #0
beq +
lda c64.SCROLY
ora #%10000000
sta c64.SCROLY ; set most significant bit of raster position
+ lda #%00000001
sta c64.IREQMASK ;enable raster interrupt signals from vic
rts
}}
}
asmsub reset_system() {
; Soft-reset the system back to initial power-on Basic prompt.
%asm {{
sei
lda #14
sta $01 ; bank the kernal in
jmp (cbm.RESET_VEC)
}}
}
asmsub wait(uword jiffies @AY) {
; --- wait approximately the given number of jiffies (1/60th seconds) (N or N+1)
; note: the system irq handler has to be active for this to work as it depends on the system jiffy clock
%asm {{
stx P8ZP_SCRATCH_B1
sta P8ZP_SCRATCH_W1
sty P8ZP_SCRATCH_W1+1
_loop lda P8ZP_SCRATCH_W1
ora P8ZP_SCRATCH_W1+1
bne +
ldx P8ZP_SCRATCH_B1
rts
+ lda cbm.TIME_LO
sta P8ZP_SCRATCH_B1
- lda cbm.TIME_LO
cmp P8ZP_SCRATCH_B1
beq -
lda P8ZP_SCRATCH_W1
bne +
dec P8ZP_SCRATCH_W1+1
+ dec P8ZP_SCRATCH_W1
jmp _loop
}}
}
asmsub waitvsync() clobbers(A) {
; --- busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
; note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
%asm {{
- bit c64.SCROLY
bpl -
- bit c64.SCROLY
bmi -
rts
}}
}
inline asmsub waitrastborder() {
; --- busy wait till the raster position has reached the bottom screen border (approximately)
; note: a more accurate way to do this is by using a raster irq handler instead.
%asm {{
- bit c64.SCROLY
bpl -
}}
}
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 irqsafe_set_irqd() {
%asm {{
php
sei
}}
}
inline asmsub irqsafe_clear_irqd() {
%asm {{
plp
}}
}
inline asmsub disable_caseswitch() {
%asm {{
lda #$80
sta 657
}}
}
inline asmsub enable_caseswitch() {
%asm {{
lda #0
sta 657
}}
}
asmsub exit(ubyte returnvalue @A) {
; -- immediately exit the program with a return code in the A register
%asm {{
sta cleanup_at_exit._exitcode
ldx prog8_lib.orig_stackpointer
txs
jmp cleanup_at_exit
}}
}
inline asmsub progend() -> uword @AY {
%asm {{
lda #<prog8_program_end
ldy #>prog8_program_end
}}
}
inline asmsub push(ubyte value @A) {
%asm {{
pha
}}
}
inline asmsub pushw(uword value @AY) {
%asm {{
pha
tya
pha
}}
}
inline asmsub pop() -> ubyte @A {
%asm {{
pla
}}
}
inline asmsub popw() -> uword @AY {
%asm {{
pla
tay
pla
}}
}
}
cx16 {
; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
; they are simulated on the C64 as well but their location in memory is different
; (because there's no room for them in the zeropage in the default configuration)
; Note that when using ZP options that free up more of the zeropage (such as %zeropage kernalsafe)
; there might be enough space to put them there after all, and the compiler will change these addresses!
&uword r0 = $cfe0
&uword r1 = $cfe2
&uword r2 = $cfe4
&uword r3 = $cfe6
&uword r4 = $cfe8
&uword r5 = $cfea
&uword r6 = $cfec
&uword r7 = $cfee
&uword r8 = $cff0
&uword r9 = $cff2
&uword r10 = $cff4
&uword r11 = $cff6
&uword r12 = $cff8
&uword r13 = $cffa
&uword r14 = $cffc
&uword r15 = $cffe
&word r0s = $cfe0
&word r1s = $cfe2
&word r2s = $cfe4
&word r3s = $cfe6
&word r4s = $cfe8
&word r5s = $cfea
&word r6s = $cfec
&word r7s = $cfee
&word r8s = $cff0
&word r9s = $cff2
&word r10s = $cff4
&word r11s = $cff6
&word r12s = $cff8
&word r13s = $cffa
&word r14s = $cffc
&word r15s = $cffe
&ubyte r0L = $cfe0
&ubyte r1L = $cfe2
&ubyte r2L = $cfe4
&ubyte r3L = $cfe6
&ubyte r4L = $cfe8
&ubyte r5L = $cfea
&ubyte r6L = $cfec
&ubyte r7L = $cfee
&ubyte r8L = $cff0
&ubyte r9L = $cff2
&ubyte r10L = $cff4
&ubyte r11L = $cff6
&ubyte r12L = $cff8
&ubyte r13L = $cffa
&ubyte r14L = $cffc
&ubyte r15L = $cffe
&ubyte r0H = $cfe1
&ubyte r1H = $cfe3
&ubyte r2H = $cfe5
&ubyte r3H = $cfe7
&ubyte r4H = $cfe9
&ubyte r5H = $cfeb
&ubyte r6H = $cfed
&ubyte r7H = $cfef
&ubyte r8H = $cff1
&ubyte r9H = $cff3
&ubyte r10H = $cff5
&ubyte r11H = $cff7
&ubyte r12H = $cff9
&ubyte r13H = $cffb
&ubyte r14H = $cffd
&ubyte r15H = $cfff
&byte r0sL = $cfe0
&byte r1sL = $cfe2
&byte r2sL = $cfe4
&byte r3sL = $cfe6
&byte r4sL = $cfe8
&byte r5sL = $cfea
&byte r6sL = $cfec
&byte r7sL = $cfee
&byte r8sL = $cff0
&byte r9sL = $cff2
&byte r10sL = $cff4
&byte r11sL = $cff6
&byte r12sL = $cff8
&byte r13sL = $cffa
&byte r14sL = $cffc
&byte r15sL = $cffe
&byte r0sH = $cfe1
&byte r1sH = $cfe3
&byte r2sH = $cfe5
&byte r3sH = $cfe7
&byte r4sH = $cfe9
&byte r5sH = $cfeb
&byte r6sH = $cfed
&byte r7sH = $cfef
&byte r8sH = $cff1
&byte r9sH = $cff3
&byte r10sH = $cff5
&byte r11sH = $cff7
&byte r12sH = $cff9
&byte r13sH = $cffb
&byte r14sH = $cffd
&byte r15sH = $cfff
asmsub save_virtual_registers() clobbers(A,Y) {
%asm {{
ldy #31
- lda cx16.r0,y
sta _cx16_vreg_storage,y
dey
bpl -
rts
_cx16_vreg_storage
.word 0,0,0,0,0,0,0,0
.word 0,0,0,0,0,0,0,0
}}
}
asmsub restore_virtual_registers() clobbers(A,Y) {
%asm {{
ldy #31
- lda save_virtual_registers._cx16_vreg_storage,y
sta cx16.r0,y
dey
bpl -
rts
}}
}
sub cpu_is_65816() -> bool {
; Returns true when you have a 65816 cpu, false when it's a 6502.
return false
}
}