mirror of
https://github.com/irmen/prog8.git
synced 2024-11-23 22:33:12 +00:00
928611eb20
For function calls, register saves go via stack (to allow nested saves) for simpler cases, registers are saved in a local variable. Fixed too agressive removal of sta-lda sequence if the lda is followed by a branching instruction. Insert missing cmp #0 after functioncall if the value of the A register is needed in a comparison expression (could otherwise test wrong status flag)
513 lines
20 KiB
Lua
513 lines
20 KiB
Lua
; Prog8 definitions for the Commodore-64
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; Including memory registers, I/O registers, Basic and Kernal subroutines.
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;
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; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
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;
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; indent format: TABS, size=8
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%target c64
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c64 {
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&ubyte TIME_HI = $a0 ; software jiffy clock, hi byte
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&ubyte TIME_MID = $a1 ; .. mid byte
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&ubyte TIME_LO = $a2 ; .. lo byte. Updated by IRQ every 1/60 sec
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&ubyte STATUS = $90 ; kernel status variable for I/O
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&ubyte STKEY = $91 ; various keyboard statuses (updated by IRQ)
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&ubyte SFDX = $cb ; current key pressed (matrix value) (updated by IRQ)
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&ubyte COLOR = $0286 ; cursor color
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&ubyte HIBASE = $0288 ; screen base address / 256 (hi-byte of screen memory address)
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&uword CINV = $0314 ; IRQ vector
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&uword NMI_VEC = $FFFA ; 6502 nmi vector, determined by the kernal if banked in
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&uword RESET_VEC = $FFFC ; 6502 reset vector, determined by the kernal if banked in
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&uword IRQ_VEC = $FFFE ; 6502 interrupt vector, determined by the kernal if banked in
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; the default addresses for the character screen chars and colors
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const uword Screen = $0400 ; to have this as an array[40*25] the compiler would have to support array size > 255
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const uword Colors = $d800 ; to have this as an array[40*25] the compiler would have to support array size > 255
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; the default locations of the 8 sprite pointers (store address of sprite / 64)
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&ubyte SPRPTR0 = 2040
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&ubyte SPRPTR1 = 2041
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&ubyte SPRPTR2 = 2042
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&ubyte SPRPTR3 = 2043
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&ubyte SPRPTR4 = 2044
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&ubyte SPRPTR5 = 2045
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&ubyte SPRPTR6 = 2046
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&ubyte SPRPTR7 = 2047
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&ubyte[8] SPRPTR = 2040 ; the 8 sprite pointers as an array.
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; ---- VIC-II 6567/6569/856x registers ----
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&ubyte SP0X = $d000
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&ubyte SP0Y = $d001
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&ubyte SP1X = $d002
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&ubyte SP1Y = $d003
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&ubyte SP2X = $d004
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&ubyte SP2Y = $d005
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&ubyte SP3X = $d006
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&ubyte SP3Y = $d007
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&ubyte SP4X = $d008
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&ubyte SP4Y = $d009
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&ubyte SP5X = $d00a
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&ubyte SP5Y = $d00b
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&ubyte SP6X = $d00c
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&ubyte SP6Y = $d00d
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&ubyte SP7X = $d00e
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&ubyte SP7Y = $d00f
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&ubyte[16] SPXY = $d000 ; the 8 sprite X and Y registers as an array.
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&uword[8] SPXYW = $d000 ; the 8 sprite X and Y registers as a combined xy word array.
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&ubyte MSIGX = $d010
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&ubyte SCROLY = $d011
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&ubyte RASTER = $d012
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&ubyte LPENX = $d013
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&ubyte LPENY = $d014
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&ubyte SPENA = $d015
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&ubyte SCROLX = $d016
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&ubyte YXPAND = $d017
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&ubyte VMCSB = $d018
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&ubyte VICIRQ = $d019
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&ubyte IREQMASK = $d01a
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&ubyte SPBGPR = $d01b
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&ubyte SPMC = $d01c
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&ubyte XXPAND = $d01d
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&ubyte SPSPCL = $d01e
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&ubyte SPBGCL = $d01f
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&ubyte EXTCOL = $d020 ; border color
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&ubyte BGCOL0 = $d021 ; screen color
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&ubyte BGCOL1 = $d022
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&ubyte BGCOL2 = $d023
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&ubyte BGCOL4 = $d024
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&ubyte SPMC0 = $d025
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&ubyte SPMC1 = $d026
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&ubyte SP0COL = $d027
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&ubyte SP1COL = $d028
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&ubyte SP2COL = $d029
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&ubyte SP3COL = $d02a
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&ubyte SP4COL = $d02b
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&ubyte SP5COL = $d02c
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&ubyte SP6COL = $d02d
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&ubyte SP7COL = $d02e
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&ubyte[8] SPCOL = $d027
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; ---- end of VIC-II registers ----
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; ---- CIA 6526 1 & 2 registers ----
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&ubyte CIA1PRA = $DC00 ; CIA 1 DRA, keyboard column drive (and joystick control port #2)
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&ubyte CIA1PRB = $DC01 ; CIA 1 DRB, keyboard row port (and joystick control port #1)
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&ubyte CIA1DDRA = $DC02 ; CIA 1 DDRA, keyboard column
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&ubyte CIA1DDRB = $DC03 ; CIA 1 DDRB, keyboard row
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&ubyte CIA1TAL = $DC04 ; CIA 1 timer A low byte
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&ubyte CIA1TAH = $DC05 ; CIA 1 timer A high byte
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&ubyte CIA1TBL = $DC06 ; CIA 1 timer B low byte
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&ubyte CIA1TBH = $DC07 ; CIA 1 timer B high byte
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&ubyte CIA1TOD10 = $DC08 ; time of day, 1/10 sec.
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&ubyte CIA1TODSEC = $DC09 ; time of day, seconds
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&ubyte CIA1TODMMIN = $DC0A ; time of day, minutes
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&ubyte CIA1TODHR = $DC0B ; time of day, hours
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&ubyte CIA1SDR = $DC0C ; Serial Data Register
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&ubyte CIA1ICR = $DC0D
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&ubyte CIA1CRA = $DC0E
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&ubyte CIA1CRB = $DC0F
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&ubyte CIA2PRA = $DD00 ; CIA 2 DRA, serial port and video address
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&ubyte CIA2PRB = $DD01 ; CIA 2 DRB, RS232 port / USERPORT
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&ubyte CIA2DDRA = $DD02 ; CIA 2 DDRA, serial port and video address
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&ubyte CIA2DDRB = $DD03 ; CIA 2 DDRB, RS232 port / USERPORT
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&ubyte CIA2TAL = $DD04 ; CIA 2 timer A low byte
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&ubyte CIA2TAH = $DD05 ; CIA 2 timer A high byte
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&ubyte CIA2TBL = $DD06 ; CIA 2 timer B low byte
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&ubyte CIA2TBH = $DD07 ; CIA 2 timer B high byte
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&ubyte CIA2TOD10 = $DD08 ; time of day, 1/10 sec.
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&ubyte CIA2TODSEC = $DD09 ; time of day, seconds
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&ubyte CIA2TODMIN = $DD0A ; time of day, minutes
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&ubyte CIA2TODHR = $DD0B ; time of day, hours
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&ubyte CIA2SDR = $DD0C ; Serial Data Register
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&ubyte CIA2ICR = $DD0D
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&ubyte CIA2CRA = $DD0E
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&ubyte CIA2CRB = $DD0F
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; ---- end of CIA registers ----
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; ---- SID 6581/8580 registers ----
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&ubyte FREQLO1 = $D400 ; channel 1 freq lo
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&ubyte FREQHI1 = $D401 ; channel 1 freq hi
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&uword FREQ1 = $D400 ; channel 1 freq (word)
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&ubyte PWLO1 = $D402 ; channel 1 pulse width lo (7-0)
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&ubyte PWHI1 = $D403 ; channel 1 pulse width hi (11-8)
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&uword PW1 = $D402 ; channel 1 pulse width (word)
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&ubyte CR1 = $D404 ; channel 1 voice control register
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&ubyte AD1 = $D405 ; channel 1 attack & decay
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&ubyte SR1 = $D406 ; channel 1 sustain & release
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&ubyte FREQLO2 = $D407 ; channel 2 freq lo
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&ubyte FREQHI2 = $D408 ; channel 2 freq hi
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&uword FREQ2 = $D407 ; channel 2 freq (word)
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&ubyte PWLO2 = $D409 ; channel 2 pulse width lo (7-0)
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&ubyte PWHI2 = $D40A ; channel 2 pulse width hi (11-8)
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&uword PW2 = $D409 ; channel 2 pulse width (word)
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&ubyte CR2 = $D40B ; channel 2 voice control register
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&ubyte AD2 = $D40C ; channel 2 attack & decay
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&ubyte SR2 = $D40D ; channel 2 sustain & release
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&ubyte FREQLO3 = $D40E ; channel 3 freq lo
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&ubyte FREQHI3 = $D40F ; channel 3 freq hi
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&uword FREQ3 = $D40E ; channel 3 freq (word)
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&ubyte PWLO3 = $D410 ; channel 3 pulse width lo (7-0)
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&ubyte PWHI3 = $D411 ; channel 3 pulse width hi (11-8)
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&uword PW3 = $D410 ; channel 3 pulse width (word)
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&ubyte CR3 = $D412 ; channel 3 voice control register
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&ubyte AD3 = $D413 ; channel 3 attack & decay
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&ubyte SR3 = $D414 ; channel 3 sustain & release
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&ubyte FCLO = $D415 ; filter cutoff lo (2-0)
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&ubyte FCHI = $D416 ; filter cutoff hi (10-3)
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&uword FC = $D415 ; filter cutoff (word)
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&ubyte RESFILT = $D417 ; filter resonance and routing
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&ubyte MVOL = $D418 ; filter mode and main volume control
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&ubyte POTX = $D419 ; potentiometer X
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&ubyte POTY = $D41A ; potentiometer Y
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&ubyte OSC3 = $D41B ; channel 3 oscillator value read
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&ubyte ENV3 = $D41C ; channel 3 envelope value read
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; ---- end of SID registers ----
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; ---- C64 ROM kernal routines ----
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romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y) ; print null-terminated string (use c64scr.print instead)
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romsub $E544 = CLEARSCR() clobbers(A,X,Y) ; clear the screen
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romsub $E566 = HOMECRSR() clobbers(A,X,Y) ; cursor to top left of screen
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romsub $EA31 = IRQDFRT() clobbers(A,X,Y) ; default IRQ routine
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romsub $EA81 = IRQDFEND() clobbers(A,X,Y) ; default IRQ end/cleanup
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romsub $FF81 = CINT() clobbers(A,X,Y) ; (alias: SCINIT) initialize screen editor and video chip
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romsub $FF84 = IOINIT() clobbers(A, X) ; initialize I/O devices (CIA, SID, IRQ)
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romsub $FF87 = RAMTAS() clobbers(A,X,Y) ; initialize RAM, tape buffer, screen
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romsub $FF8A = RESTOR() clobbers(A,X,Y) ; restore default I/O vectors
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romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y) ; read/set I/O vector table
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romsub $FF90 = SETMSG(ubyte value @ A) ; set Kernal message control flag
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romsub $FF93 = SECOND(ubyte address @ A) clobbers(A) ; (alias: LSTNSA) send secondary address after LISTEN
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romsub $FF96 = TKSA(ubyte address @ A) clobbers(A) ; (alias: TALKSA) send secondary address after TALK
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romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY ; read/set top of memory pointer
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romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY ; read/set bottom of memory pointer
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romsub $FF9F = SCNKEY() clobbers(A,X,Y) ; scan the keyboard
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romsub $FFA2 = SETTMO(ubyte timeout @ A) ; set time-out flag for IEEE bus
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romsub $FFA5 = ACPTR() -> ubyte @ A ; (alias: IECIN) input byte from serial bus
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romsub $FFA8 = CIOUT(ubyte databyte @ A) ; (alias: IECOUT) output byte to serial bus
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romsub $FFAB = UNTLK() clobbers(A) ; command serial bus device to UNTALK
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romsub $FFAE = UNLSN() clobbers(A) ; command serial bus device to UNLISTEN
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romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A) ; command serial bus device to LISTEN
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romsub $FFB4 = TALK(ubyte device @ A) clobbers(A) ; command serial bus device to TALK
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romsub $FFB7 = READST() -> ubyte @ A ; read I/O status word
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romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y) ; set logical file parameters
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romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY) ; set filename parameters
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romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A ; (via 794 ($31A)) open a logical file
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romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y) ; (via 796 ($31C)) close a logical file
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romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> ubyte @Pc ; (via 798 ($31E)) define an input channel
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romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X) ; (via 800 ($320)) define an output channel
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romsub $FFCC = CLRCHN() clobbers(A,X) ; (via 802 ($322)) restore default devices
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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.
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romsub $FFD2 = CHROUT(ubyte char @ A) ; (via 806 ($326)) output a character
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romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y ; (via 816 ($330)) load from device
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romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A ; (via 818 ($332)) save to a device
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romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y) ; set the software clock
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romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y ; read the software clock
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romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A ; (via 808 ($328)) check the STOP key (and some others in A)
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romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A ; (via 810 ($32A)) get a character
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romsub $FFE7 = CLALL() clobbers(A,X) ; (via 812 ($32C)) close all files
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romsub $FFEA = UDTIM() clobbers(A,X) ; update the software clock
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romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y ; read number of screen rows and columns
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romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y ; read/set position of cursor on screen. Use txt.plot for a 'safe' wrapper that preserves X.
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romsub $FFF3 = IOBASE() -> uword @ XY ; read base address of I/O devices
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; ---- end of C64 ROM kernal routines ----
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; ---- utilities -----
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asmsub STOP2() -> ubyte @A {
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; -- check if STOP key was pressed, returns true if so. More convenient to use than STOP() because that only sets the carry status flag.
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%asm {{
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txa
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pha
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jsr c64.STOP
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beq +
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pla
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tax
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lda #0
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rts
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+ pla
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tax
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lda #1
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rts
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}}
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}
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; ---- C64 specific system utility routines: ----
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asmsub init_system() {
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; Initializes the machine to a sane starting state.
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; Called automatically by the loader program logic.
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; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
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; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
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; Also a different color scheme is chosen to identify ourselves a little.
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; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
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%asm {{
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sei
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cld
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lda #%00101111
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sta $00
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lda #%00100111
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sta $01
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jsr c64.IOINIT
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jsr c64.RESTOR
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jsr c64.CINT
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lda #6
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sta c64.EXTCOL
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lda #7
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sta c64.COLOR
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lda #0
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sta c64.BGCOL0
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jsr disable_runstop_and_charsetswitch
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clc
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clv
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cli
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rts
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}}
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}
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asmsub reset_system() {
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; Soft-reset the system back to Basic prompt.
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%asm {{
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sei
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lda #14
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sta $01 ; bank the kernal in
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jmp (c64.RESET_VEC)
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}}
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}
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sub wait(uword jiffies) {
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uword current_time = 0
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c64.SETTIM(0,0,0)
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while current_time < jiffies {
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; read clock
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%asm {{
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stx P8ZP_SCRATCH_REG
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jsr c64.RDTIM
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sta current_time
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stx current_time+1
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ldx P8ZP_SCRATCH_REG
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}}
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}
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}
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asmsub disable_runstop_and_charsetswitch() {
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%asm {{
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lda #$80
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sta 657 ; disable charset switching
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lda #239
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sta 808 ; disable run/stop key
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rts
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}}
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}
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asmsub set_irqvec_excl() clobbers(A) {
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%asm {{
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sei
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lda #<_irq_handler
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sta c64.CINV
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lda #>_irq_handler
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sta c64.CINV+1
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cli
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rts
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_irq_handler jsr set_irqvec._irq_handler_init
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jsr irq.irq
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jsr set_irqvec._irq_handler_end
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lda #$ff
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sta c64.VICIRQ ; acknowledge raster irq
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lda c64.CIA1ICR ; acknowledge CIA1 interrupt
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jmp c64.IRQDFEND ; end irq processing - don't call kernel
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}}
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}
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asmsub set_irqvec() clobbers(A) {
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%asm {{
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sei
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lda #<_irq_handler
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sta c64.CINV
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lda #>_irq_handler
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sta c64.CINV+1
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cli
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rts
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_irq_handler jsr _irq_handler_init
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jsr irq.irq
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jsr _irq_handler_end
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jmp c64.IRQDFRT ; continue with normal kernel irq routine
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_irq_handler_init
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; save all zp scratch registers and the X register as these might be clobbered by the irq routine
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stx IRQ_X_REG
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lda P8ZP_SCRATCH_B1
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sta IRQ_SCRATCH_ZPB1
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lda P8ZP_SCRATCH_REG
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sta IRQ_SCRATCH_ZPREG
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lda P8ZP_SCRATCH_W1
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sta IRQ_SCRATCH_ZPWORD1
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lda P8ZP_SCRATCH_W1+1
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sta IRQ_SCRATCH_ZPWORD1+1
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lda P8ZP_SCRATCH_W2
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sta IRQ_SCRATCH_ZPWORD2
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lda P8ZP_SCRATCH_W2+1
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sta IRQ_SCRATCH_ZPWORD2+1
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; stack protector; make sure we don't clobber the top of the evaluation stack
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dex
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dex
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dex
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dex
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dex
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dex
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cld
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rts
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_irq_handler_end
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; restore all zp scratch registers and the X register
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lda IRQ_SCRATCH_ZPB1
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sta P8ZP_SCRATCH_B1
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lda IRQ_SCRATCH_ZPREG
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sta P8ZP_SCRATCH_REG
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lda IRQ_SCRATCH_ZPWORD1
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sta P8ZP_SCRATCH_W1
|
|
lda IRQ_SCRATCH_ZPWORD1+1
|
|
sta P8ZP_SCRATCH_W1+1
|
|
lda IRQ_SCRATCH_ZPWORD2
|
|
sta P8ZP_SCRATCH_W2
|
|
lda IRQ_SCRATCH_ZPWORD2+1
|
|
sta P8ZP_SCRATCH_W2+1
|
|
ldx IRQ_X_REG
|
|
rts
|
|
|
|
IRQ_X_REG .byte 0
|
|
IRQ_SCRATCH_ZPB1 .byte 0
|
|
IRQ_SCRATCH_ZPREG .byte 0
|
|
IRQ_SCRATCH_ZPWORD1 .word 0
|
|
IRQ_SCRATCH_ZPWORD2 .word 0
|
|
|
|
}}
|
|
}
|
|
|
|
asmsub restore_irqvec() {
|
|
%asm {{
|
|
sei
|
|
lda #<c64.IRQDFRT
|
|
sta c64.CINV
|
|
lda #>c64.IRQDFRT
|
|
sta c64.CINV+1
|
|
lda #0
|
|
sta c64.IREQMASK ; disable raster irq
|
|
lda #%10000001
|
|
sta c64.CIA1ICR ; restore CIA1 irq
|
|
cli
|
|
rts
|
|
}}
|
|
}
|
|
|
|
asmsub set_rasterirq(uword rasterpos @ AY) clobbers(A) {
|
|
%asm {{
|
|
sei
|
|
jsr _setup_raster_irq
|
|
lda #<_raster_irq_handler
|
|
sta c64.CINV
|
|
lda #>_raster_irq_handler
|
|
sta c64.CINV+1
|
|
cli
|
|
rts
|
|
|
|
_raster_irq_handler
|
|
jsr set_irqvec._irq_handler_init
|
|
jsr irq.irq
|
|
jsr set_irqvec._irq_handler_end
|
|
lda #$ff
|
|
sta c64.VICIRQ ; acknowledge raster irq
|
|
jmp c64.IRQDFRT
|
|
|
|
_setup_raster_irq
|
|
pha
|
|
lda #%01111111
|
|
sta c64.CIA1ICR ; "switch off" interrupts signals from cia-1
|
|
sta c64.CIA2ICR ; "switch off" interrupts signals from cia-2
|
|
and c64.SCROLY
|
|
sta c64.SCROLY ; clear most significant bit of raster position
|
|
lda c64.CIA1ICR ; ack previous irq
|
|
lda c64.CIA2ICR ; ack previous irq
|
|
pla
|
|
sta c64.RASTER ; set the raster line number where interrupt should occur
|
|
cpy #0
|
|
beq +
|
|
lda c64.SCROLY
|
|
ora #%10000000
|
|
sta c64.SCROLY ; set most significant bit of raster position
|
|
+ lda #%00000001
|
|
sta c64.IREQMASK ;enable raster interrupt signals from vic
|
|
rts
|
|
}}
|
|
}
|
|
|
|
asmsub set_rasterirq_excl(uword rasterpos @ AY) clobbers(A) {
|
|
%asm {{
|
|
sei
|
|
jsr set_rasterirq._setup_raster_irq
|
|
lda #<_raster_irq_handler
|
|
sta c64.CINV
|
|
lda #>_raster_irq_handler
|
|
sta c64.CINV+1
|
|
cli
|
|
rts
|
|
|
|
_raster_irq_handler
|
|
jsr set_irqvec._irq_handler_init
|
|
jsr irq.irq
|
|
jsr set_irqvec._irq_handler_end
|
|
lda #$ff
|
|
sta c64.VICIRQ ; acknowledge raster irq
|
|
jmp c64.IRQDFEND ; end irq processing - don't call kernel
|
|
|
|
}}
|
|
}
|
|
|
|
; ---- end of C64 specific system utility routines ----
|
|
|
|
|
|
}
|
|
|
|
|
|
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)
|
|
; they are allocated at the bottom of the eval-stack (should be ample space unless
|
|
; you're doing insane nesting of expressions...)
|
|
&uword r0 = $cf00
|
|
&uword r1 = $cf02
|
|
&uword r2 = $cf04
|
|
&uword r3 = $cf06
|
|
&uword r4 = $cf08
|
|
&uword r5 = $cf0a
|
|
&uword r6 = $cf0c
|
|
&uword r7 = $cf0e
|
|
&uword r8 = $cf10
|
|
&uword r9 = $cf12
|
|
&uword r10 = $cf14
|
|
&uword r11 = $cf16
|
|
&uword r12 = $cf18
|
|
&uword r13 = $cf1a
|
|
&uword r14 = $cf1c
|
|
&uword r15 = $cf1e
|
|
|
|
}
|