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tutorial part 1

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This commit is contained in:
Greg Shuflin 2022-06-13 16:00:17 -07:00
parent 6c2e4cee5a
commit dba3191aa2
8 changed files with 390 additions and 0 deletions
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1
.gitignore vendored
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*.swp
*.smc
*.obj
out/

30
homebrew-tutorial/header.asm Normal file
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.segment "HEADER"
.byte "GNOSTIKKA " ; ROM name, must be 21 chars
.byte $30 ; Map Mode: 3.58MHz LoROM
.byte $00 ; Cartridge Type: ROM only
.byte $08 ; ROM Size
.byte $00 ; RAM size
.byte $01 ; Destination Code: USA
.byte $33 ; Fixed value
.byte $00 ; Mask ROM Version
.word $0000 ; Complement Check
.word $0000 ; Check Sum
; native mode vectors
.word 0, 0
.addr _rti ; COP
.addr _rti ; BRK
.addr _rti ; ABORT
.addr nmi ; NMI
.addr start ; RST
.addr _rti ; IRQ
; emulation mode vectors - largely unused, since we run in native mode
.word 0, 0
.addr 0
.addr 0
.addr 0
.addr 0
.addr start ; RST
.addr 0

49
homebrew-tutorial/init.asm Normal file
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; A very simple SNES init routine
; For serious use, you probably want to do more than this
; This is simple and understandable, though
; Will leave you in A8 XY16 mode
; Disable interrupts and enable native (i.e. not 6502-emulating) mode
sei
clc
xce
cld
setAXY16
; ZeroCPU registers NMITIMEN through MEMSEL
stz $4200
stz $4202
stz $4204
stz $4206
stz $4208
stz $420A
stz $420C
lda #$0080
sta INIDISP ; Turn off screen ("forced blank")
; Zero some registers used for rendering
stz OAMADDL
stz BGMODE
stz BG1SC
stz BG3SC
stz BG12NBA
stz VMADDL
stz W12SEL
stz WH0
stz WH2
stz WBGLOG
stz TM
stz TMW
; Disable color math / etc
ldx #$0030
stx CGWSEL
ldy #$00E0
sty COLDATA
setA8
; Zero window masks
stz WOBJSEL

33
homebrew-tutorial/lorom.cfg Normal file
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MEMORY {
ZEROPAGE: start = $000000, size = $0100;
STACK: start = $000100, size = $0100;
BSS: start = $000200, size = $1E00;
BSS7E: start = $7E2000, size = $E000;
BSS7F: start = $7F0000, size =$10000;
ROM0: start = $808000, size = $8000, fill = yes;
ROM1: start = $818000, size = $8000, fill = yes;
ROM2: start = $828000, size = $8000, fill = yes;
ROM3: start = $838000, size = $8000, fill = yes;
ROM4: start = $848000, size = $8000, fill = yes;
ROM5: start = $858000, size = $8000, fill = yes;
ROM6: start = $868000, size = $8000, fill = yes;
ROM7: start = $878000, size = $8000, fill = yes;
}
SEGMENTS {
CODE: load = ROM0, align = $100;
HEADER: load = ROM0, start = $80FFC0;
CODE1: load = ROM1, align = $100, optional=yes;
CODE2: load = ROM2, align = $100, optional=yes;
CODE3: load = ROM3, align = $100, optional=yes;
CODE4: load = ROM4, align = $100, optional=yes;
CODE5: load = ROM5, align = $100, optional=yes;
CODE6: load = ROM6, align = $100, optional=yes;
CODE7: load = ROM7, align = $100, optional=yes;
ZEROPAGE: load = ZEROPAGE, type = zp, define=yes;
BSS: load = BSS, type = bss, align = $100, optional=yes;
BSS7E: load = BSS7E, type = bss, align = $100, optional=yes;
BSS7F: load = BSS7F, type = bss, align = $100, optional=yes;
}

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homebrew-tutorial/macros.inc Normal file
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.macro setA8
sep #$20
.endmacro
.macro setA16
rep #$20
.endmacro
.macro setAXY8
sep #$30
.endmacro
.macro setAXY16
rep #$30
.endmacro
.macro setXY8
sep #$10
.endmacro
.macro setXY16
rep #$10
.endmacro

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homebrew-tutorial/main.asm Normal file
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.p816
.smart
.include "macros.inc"
.include "registers.inc"
.include "header.asm"
.segment "CODE"
start:
.include "init.asm"
; Set up the color palette
stz CGADD
; Set color zero to red
; $001f = %0000000000011111
; bbbbbgggggrrrrr
lda #$1f
sta CGDATA
lda #$00
sta CGDATA
lda #$0f
sta INIDISP
busywait:
bra busywait
nmi:
bit RDNMI
_rti:
rti

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homebrew-tutorial/registers.inc Normal file
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; SNES Register Aliases
; Address Bus B Registers
INIDISP = $2100 ; Screen Display Register single write any time
OBSEL = $2101 ; Object Size and Character Size Register single write f-blank, v-blank
OAMADDL = $2102 ; OAM Address Registers (Low) single write f-blank, v-blank
OAMADDH = $2103 ; OAM Address Registers (High) single write f-blank, v-blank
OAMDATA = $2104 ; OAM Data Write Register single write f-blank, v-blank
BGMODE = $2105 ; BG Mode and Character Size Register single write f-blank, v-blank, h-blank
MOSAIC = $2106 ; Mosaic Register single write f-blank, v-blank, h-blank
BG1SC = $2107 ; BG Tilemap Address Registers (BG1) single write f-blank, v-blank
BG2SC = $2108 ; BG Tilemap Address Registers (BG2) single write f-blank, v-blank
BG3SC = $2109 ; BG Tilemap Address Registers (BG3) single write f-blank, v-blank
BG4SC = $210A ; BG Tilemap Address Registers (BG4) single write f-blank, v-blank
BG12NBA = $210B ; BG Character Address Registers (BG1&2) single write f-blank, v-blank
BG34NBA = $210C ; BG Character Address Registers (BG3&4) single write f-blank, v-blank
BG1HOFS = $210D ; BG Scroll Registers (BG1) dual write f-blank, v-blank, h-blank
BG1VOFS = $210E ; BG Scroll Registers (BG1) dual write f-blank, v-blank, h-blank
BG2HOFS = $210F ; BG Scroll Registers (BG2) dual write f-blank, v-blank, h-blank
BG2VOFS = $2110 ; BG Scroll Registers (BG2) dual write f-blank, v-blank, h-blank
BG3HOFS = $2111 ; BG Scroll Registers (BG3) dual write f-blank, v-blank, h-blank
BG3VOFS = $2112 ; BG Scroll Registers (BG3) dual write f-blank, v-blank, h-blank
BG4HOFS = $2113 ; BG Scroll Registers (BG4) dual write f-blank, v-blank, h-blank
BG4VOFS = $2114 ; BG Scroll Registers (BG4) dual write f-blank, v-blank, h-blank
VMAIN = $2115 ; Video Port Control Register single write f-blank, v-blank
VMADDL = $2116 ; VRAM Address Registers (Low) single write f-blank, v-blank
VMADDH = $2117 ; VRAM Address Registers (High) single write f-blank, v-blank
VMDATAL = $2118 ; VRAM Data Write Registers (Low) single write f-blank, v-blank
VMDATAH = $2119 ; VRAM Data Write Registers (High) single write f-blank, v-blank
M7SEL = $211A ; Mode 7 Settings Register single write f-blank, v-blank
M7A = $211B ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
M7B = $211C ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
M7C = $211D ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
M7D = $211E ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
M7X = $211F ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
M7Y = $2120 ; Mode 7 Matrix Registers dual write f-blank, v-blank, h-blank
CGADD = $2121 ; CGRAM Address Register single write f-blank, v-blank, h-blank
CGDATA = $2122 ; CGRAM Data Write Register dual write f-blank, v-blank, h-blank
W12SEL = $2123 ; Window Mask Settings Registers single write f-blank, v-blank, h-blank
W34SEL = $2124 ; Window Mask Settings Registers single write f-blank, v-blank, h-blank
WOBJSEL = $2125 ; Window Mask Settings Registers single write f-blank, v-blank, h-blank
WH0 = $2126 ; Window Position Registers (WH0) single write f-blank, v-blank, h-blank
WH1 = $2127 ; Window Position Registers (WH1) single write f-blank, v-blank, h-blank
WH2 = $2128 ; Window Position Registers (WH2) single write f-blank, v-blank, h-blank
WH3 = $2129 ; Window Position Registers (WH3) single write f-blank, v-blank, h-blank
WBGLOG = $212A ; Window Mask Logic registers (BG) single write f-blank, v-blank, h-blank
WOBJLOG = $212B ; Window Mask Logic registers (OBJ) single write f-blank, v-blank, h-blank
TM = $212C ; Screen Destination Registers single write f-blank, v-blank, h-blank
TS = $212D ; Screen Destination Registers single write f-blank, v-blank, h-blank
TMW = $212E ; Window Mask Destination Registers single write f-blank, v-blank, h-blank
TSW = $212F ; Window Mask Destination Registers single write f-blank, v-blank, h-blank
CGWSEL = $2130 ; Color Math Registers single write f-blank, v-blank, h-blank
CGADSUB = $2131 ; Color Math Registers single write f-blank, v-blank, h-blank
COLDATA = $2132 ; Color Math Registers single write f-blank, v-blank, h-blank
SETINI = $2133 ; Screen Mode Select Register single write f-blank, v-blank, h-blank
MPYL = $2134 ; Multiplication Result Registers single read f-blank, v-blank, h-blank
MPYM = $2135 ; Multiplication Result Registers single read f-blank, v-blank, h-blank
MPYH = $2136 ; Multiplication Result Registers single read f-blank, v-blank, h-blank
SLHV = $2137 ; Software Latch Register single any time
OAMDATAREAD = $2138 ; OAM Data Read Register dual read f-blank, v-blank
VMDATALREAD = $2139 ; VRAM Data Read Register (Low) single read f-blank, v-blank
VMDATAHREAD = $213A ; VRAM Data Read Register (High) single read f-blank, v-blank
CGDATAREAD = $213B ; CGRAM Data Read Register dual read f-blank, v-blank
OPHCT = $213C ; Scanline Location Registers (Horizontal) dual read any time
OPVCT = $213D ; Scanline Location Registers (Vertical) dual read any time
STAT77 = $213E ; PPU Status Register single read any time
STAT78 = $213F ; PPU Status Register single read any time
APUIO0 = $2140 ; APU IO Registers single both any time
APUIO1 = $2141 ; APU IO Registers single both any time
APUIO2 = $2142 ; APU IO Registers single both any time
APUIO3 = $2143 ; APU IO Registers single both any time
WMDATA = $2180 ; WRAM Data Register single both any time
WMADDL = $2181 ; WRAM Address Registers single write any time
WMADDM = $2182 ; WRAM Address Registers single write any time
WMADDH = $2183 ; WRAM Address Registers single write any time
; Old Style Joypad Registers
JOYSER0 = $4016 ; Old Style Joypad Registers single (write) read/write any time that is not auto-joypad
JOYSER1 = $4017 ; Old Style Joypad Registers many (read) read any time that is not auto-joypad
; Internal CPU Registers
NMITIMEN = $4200 ; Interrupt Enable Register single write any time
WRIO = $4201 ; IO Port Write Register single write any time
WRMPYA = $4202 ; Multiplicand Registers single write any time
WRMPYB = $4203 ; Multiplicand Registers single write any time
WRDIVL = $4204 ; Divisor & Dividend Registers single write any time
WRDIVH = $4205 ; Divisor & Dividend Registers single write any time
WRDIVB = $4206 ; Divisor & Dividend Registers single write any time
HTIMEL = $4207 ; IRQ Timer Registers (Horizontal - Low) single write any time
HTIMEH = $4208 ; IRQ Timer Registers (Horizontal - High) single write any time
VTIMEL = $4209 ; IRQ Timer Registers (Vertical - Low) single write any time
VTIMEH = $420A ; IRQ Timer Registers (Vertical - High) single write any time
MDMAEN = $420B ; DMA Enable Register single write any time
HDMAEN = $420C ; HDMA Enable Register single write any time
MEMSEL = $420D ; ROM Speed Register single write any time
RDNMI = $4210 ; Interrupt Flag Registers single read any time
TIMEUP = $4211 ; Interrupt Flag Registers single read any time
HVBJOY = $4212 ; PPU Status Register single read any time
RDIO = $4213 ; IO Port Read Register single read any time
RDDIVL = $4214 ; Multiplication Or Divide Result Registers (Low) single read any time
RDDIVH = $4215 ; Multiplication Or Divide Result Registers (High) single read any time
RDMPYL = $4216 ; Multiplication Or Divide Result Registers (Low) single read any time
RDMPYH = $4217 ; Multiplication Or Divide Result Registers (High) single read any time
JOY1L = $4218 ; Controller Port Data Registers (Pad 1 - Low) single read any time that is not auto-joypad
JOY1H = $4219 ; Controller Port Data Registers (Pad 1 - High) single read any time that is not auto-joypad
JOY2L = $421A ; Controller Port Data Registers (Pad 2 - Low) single read any time that is not auto-joypad
JOY2H = $421B ; Controller Port Data Registers (Pad 2 - High) single read any time that is not auto-joypad
JOY3L = $421C ; Controller Port Data Registers (Pad 3 - Low) single read any time that is not auto-joypad
JOY3H = $421D ; Controller Port Data Registers (Pad 3 - High) single read any time that is not auto-joypad
JOY4L = $421E ; Controller Port Data Registers (Pad 4 - Low) single read any time that is not auto-joypad
JOY4H = $421F ; Controller Port Data Registers (Pad 4 - High) single read any time that is not auto-joypad
; DMA/HDMA Registers
DMAP0 = $4300 ; (H)DMA Control Register
BBAD0 = $4301 ; (H)DMA Destination Register
A1T0L = $4302 ; (H)DMA Source Address Registers
A1T0H = $4303 ; (H)DMA Source Address Registers
A1B0 = $4304 ; (H)DMA Source Address Registers
DAS0L = $4305 ; (H)DMA Size Registers (Low)
DAS0H = $4306 ; (H)DMA Size Registers (High)
DASB0 = $4307 ; HDMA Indirect Address Registers
A2A0L = $4308 ; HDMA Mid Frame Table Address Registers (Low)
A2A0H = $4309 ; HDMA Mid Frame Table Address Registers (High)
NTLR0 = $430A ; HDMA Line Counter Register
DMAP1 = $4310 ; (H)DMA Control Register
BBAD1 = $4311 ; (H)DMA Destination Register
A1T1L = $4312 ; (H)DMA Source Address Registers
A1T1H = $4313 ; (H)DMA Source Address Registers
A1B1 = $4314 ; (H)DMA Source Address Registers
DAS1L = $4315 ; (H)DMA Size Registers (Low)
DAS1H = $4316 ; (H)DMA Size Registers (High)
DASB1 = $4317 ; HDMA Indirect Address Registers
A2A1L = $4318 ; HDMA Mid Frame Table Address Registers (Low)
A2A1H = $4319 ; HDMA Mid Frame Table Address Registers (High)
NTLR1 = $431A ; HDMA Line Counter Register
DMAP2 = $4320 ; (H)DMA Control Register
BBAD2 = $4321 ; (H)DMA Destination Register
A1T2L = $4322 ; (H)DMA Source Address Registers
A1T2H = $4323 ; (H)DMA Source Address Registers
A1B2 = $4324 ; (H)DMA Source Address Registers
DAS2L = $4325 ; (H)DMA Size Registers (Low)
DAS2H = $4326 ; (H)DMA Size Registers (High)
DASB2 = $4327 ; HDMA Indirect Address Registers
A2A2L = $4328 ; HDMA Mid Frame Table Address Registers (Low)
A2A2H = $4329 ; HDMA Mid Frame Table Address Registers (High)
NTLR2 = $432A ; HDMA Line Counter Register
DMAP3 = $4330 ; (H)DMA Control Register
BBAD3 = $4331 ; (H)DMA Destination Register
A1T3L = $4332 ; (H)DMA Source Address Registers
A1T3H = $4333 ; (H)DMA Source Address Registers
A1B3 = $4334 ; (H)DMA Source Address Registers
DAS3L = $4335 ; (H)DMA Size Registers (Low)
DAS3H = $4336 ; (H)DMA Size Registers (High)
DASB3 = $4337 ; HDMA Indirect Address Registers
A2A3L = $4338 ; HDMA Mid Frame Table Address Registers (Low)
A2A3H = $4339 ; HDMA Mid Frame Table Address Registers (High)
NTLR3 = $433A ; HDMA Line Counter Register
DMAP4 = $4340 ; (H)DMA Control Register
BBAD4 = $4341 ; (H)DMA Destination Register
A1T4L = $4342 ; (H)DMA Source Address Registers
A1T4H = $4343 ; (H)DMA Source Address Registers
A1B4 = $4344 ; (H)DMA Source Address Registers
DAS4L = $4345 ; (H)DMA Size Registers (Low)
DAS4H = $4346 ; (H)DMA Size Registers (High)
DASB4 = $4347 ; HDMA Indirect Address Registers
A2A4L = $4348 ; HDMA Mid Frame Table Address Registers (Low)
A2A4H = $4349 ; HDMA Mid Frame Table Address Registers (High)
NTLR4 = $434A ; HDMA Line Counter Register
DMAP5 = $4350 ; (H)DMA Control Register
BBAD5 = $4351 ; (H)DMA Destination Register
A1T5L = $4352 ; (H)DMA Source Address Registers
A1T5H = $4353 ; (H)DMA Source Address Registers
A1B5 = $4354 ; (H)DMA Source Address Registers
DAS5L = $4355 ; (H)DMA Size Registers (Low)
DAS5H = $4356 ; (H)DMA Size Registers (High)
DASB5 = $4357 ; HDMA Indirect Address Registers
A2A5L = $4358 ; HDMA Mid Frame Table Address Registers (Low)
A2A5H = $4359 ; HDMA Mid Frame Table Address Registers (High)
NTLR5 = $435A ; HDMA Line Counter Register
DMAP6 = $4360 ; (H)DMA Control Register
BBAD6 = $4361 ; (H)DMA Destination Register
A1T6L = $4362 ; (H)DMA Source Address Registers
A1T6H = $4363 ; (H)DMA Source Address Registers
A1B6 = $4364 ; (H)DMA Source Address Registers
DAS6L = $4365 ; (H)DMA Size Registers (Low)
DAS6H = $4366 ; (H)DMA Size Registers (High)
DASB6 = $4367 ; HDMA Indirect Address Registers
A2A6L = $4368 ; HDMA Mid Frame Table Address Registers (Low)
A2A6H = $4369 ; HDMA Mid Frame Table Address Registers (High)
NTLR6 = $436A ; HDMA Line Counter Register
DMAP7 = $4370 ; (H)DMA Control Register
BBAD7 = $4371 ; (H)DMA Destination Register
A1T7L = $4372 ; (H)DMA Source Address Registers
A1T7H = $4373 ; (H)DMA Source Address Registers
A1B7 = $4374 ; (H)DMA Source Address Registers
DAS7L = $4375 ; (H)DMA Size Registers (Low)
DAS7H = $4376 ; (H)DMA Size Registers (High)
DASB7 = $4377 ; HDMA Indirect Address Registers
A2A7L = $4378 ; HDMA Mid Frame Table Address Registers (Low)
A2A7H = $4379 ; HDMA Mid Frame Table Address Registers (High)
NTLR7 = $437A ; HDMA Line Counter Register

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justfile
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default:
just --list
homebrew-tutorial:
mkdir -p out
ca65 ./homebrew-tutorial/main.asm -o ./out/main.o -g
ld65 -C ./homebrew-tutorial/lorom.cfg -o ./out/main.sfc ./out/main.o
greenspace_smc:
just legacy/greenspace/greenspace_smc