beta.2

.gitmodules

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+[submodule "tools/bass-src"]
+	path = tools/bass-src
+	url = https://github.com/ARM9/bass

LICENSE.txt

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+Copyright 2020 Adam Gashlin (hcs)
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Makefile

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+.PHONY: all ntsc ntsc_sym pal pkg clean clean-tools clean-all
+
+TOOLS=tools/chksum64 tools/bass
+
+# Path relative to src/
+BASS=../tools/bass
+CHKSUM64=./tools/chksum64
+
+ERR_EMBED=-d 'ERR_EMBED1=../pkg/roms/nestify7.nes' -d 'ERR_EMBED2=../pkg/roms/efp6.nes'
+NTSC_BASS_CMD=$(BASS) neon64.asm -d 'NTSC_NES=1' $(ERR_EMBED) -d 'OUTPUT_FILE=../neon64bu.rom'
+
+ntsc: $(TOOLS)
+	cd src ; $(NTSC_BASS_CMD)
+	$(CHKSUM64) neon64bu.rom
+
+ntsc_sym:
+	cd src ; $(NTSC_BASS_CMD) -sym neon64.sym
+	sort src/neon64.sym > src/neon64.sym.sorted
+	mv src/neon64.sym.sorted src/neon64.sym
+
+all: ntsc pal
+
+clean-all: clean clean-tools
+
+pal: $(TOOLS)
+	cd src ; $(BASS) neon64.asm -d 'PAL_NES=1' -d 'OUTPUT_FILE=../neon64bu_pal.rom'
+	$(CHKSUM64) neon64bu_pal.rom
+
+pkg: ntsc pal
+	zip --junk-paths neon64v2XXXX.zip pkg/README.txt LICENSE.txt neon64bu.rom neon64bu_pal.rom
+
+clean:
+	rm -f neon64bu.rom neon64bu_pal.rom src/neon64.sym neon64v2XXXX.zip
+
+tools/chksum64: tools/chksum64.c
+
+tools/bass:
+	git submodule init
+	git submodule update
+	$(MAKE) -C tools/bass-src/bass/
+	cp tools/bass-src/bass/bass tools/bass
+
+clean-tools:
+	rm -f tools/chksum64 tools/bass
+	$(MAKE) -C tools/bass-src/bass/ clean

pkg/README.txt

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+Neon64 2.0 beta 2
+=================
+
+NES Emulation, On the N64, in the distant future...
+
+Features
+--------
+
+- NTSC NES on NTSC N64
+- CPU (official opcodes)
+- PPU
+- APU channels (2 square, triangle, noise, DMC)
+- Battery backed RAM save to SRAM
+- iNES mappers #s 0,1,2,3,4,7,30,31,71
+- Controller 1 (D-pad + analog)
+
+There's a lot missing, but it's already worlds better than 1.2.
+
+Running
+-------
+
+The easiest way is to use a dev cart that supports using an NES emulator for
+.nes files:
+
+- 64drive: Drop neon64bu.rom into the root directory.
+- EverDrive-64: Rename neon64bu.rom to emu.nes and put it in the ED64 directory.
+
+Anything that loads the NES ROM at the "emulation standard" (0x200000) will work.
+
+The Neon64 ROM is only as long as it needs to be to be checksummed consistently,
+so it will also look for a NES ROM at 0x101000 so it can be directly appended.
+From a Windows command line:
+
+copy /b neon64bu.rom + game.nes game.n64
+
+on Linux, macOS, etc:
+
+cat neon64bu.rom game.nes > game.n64
+
+I've included a separate version with PAL NES timing, this is usable but janky.
+
+Controls
+--------
+
+A, B, Start and the D-pad on controller 1 are mapped in the obvious way. Select
+is the Z button. The analog stick is roughly like the D-pad, it may be easier to
+use with games allowing diagonal movement.
+
+To access the menu, hold the L and R shoulder buttons. Navigate with the D-pad
+or Z, select an option with A or Start. Hold L and R again to dismiss the menu.
+
+Saving
+------
+
+For games with battery-backed RAM, you can save from the menu.
+
+Saving uses dedicated 768Kbit SRAM. This is supported by newer 64drive firmware,
+tested with 1.14e.
+
+Saves should be compatible with Visor's "Neon64 with Savestates" 0.3c, though
+savestates are not yet supported.
+
+Architecture
+------------
+
+I split up the 6502 CPU ops to reduce code size; all N64 CPU code fits in ICache
+(1.5K to spare). All ucode fits in IMEM together (200 bytes to spare).
+
+The CPU runs the main PPU loop. It passes the bytes read to the RSP, which
+converts the background to a 4bpp texture and arranges sprites in an 8bpp
+texture.
+
+The RDP renders each frame, layering sprites and background, with tricky
+palettes to use the same texture for BG and FG sprites.
+
+The RSP synthesizes audio, driven by alists from the CPU. When the PCM buffer
+runs low, the AI interrupt can request an immediate flush to stretch the alist.
+
+The CPU has a cooperative scheduler, using an emulated cycle timer to trade off
+between the CPU and PPU. This works mainly with daddi+bgezl.
+
+The RSP has a separate coop scheduler. When a task yields it can run code on the
+CPU via the RSP break interrupt.
+
+I use the TLB to swap and mirror banks (PC is a native pointer), write protect
+CHR ROM, place data at addresses below 32K (for free indexing), and mirror all
+RDRAM (so bit 31 can be used as a flag).
+
+On most games only around 50% of frame time is used.
+
+Version history
+---------------
+
+2020-07-07 - beta 2
+  - Add mappers 30, 31, 71
+  - Source release
+
+2020-07-04 - beta 1
+  - Initial beta release
+
+Everybody
+---------
+
+Thanks to:
+* blargg for many docs and tests
+* Marat Fayzullin for teaching a generation about emulation
+* krom for great source and discussion
+* MarathonMan et al for cen64 (very helpful for debugging!)
+* marshallh for 64drive (the best N64 dev tool!)
+* Near, ARM9, et al for bass
+* Visor for a lot of good patches to 1.2
+* Eisi for adding MMC4 support in 1.2
+* bootgod et al for NesCartDB
+
+Many thanks to contributors to the NesDev wiki and ultra64.ca.
+
+Greets to the #n64dev and N64brew sceners, LaC, Pinchy, Zoinkity, jrra,
+mikeryan, ppcasm, arbin, DragonMinded, level42, fraser, fin, CrashOverride,
+et al!
+
+Hello to my HCS Forum friends, bxaimc, knurek, FastElbja, manakoAT, kode54,
+bnnm, Josh W, Mouser_X, and unknownfile if you're still out there!
+
+Black Lives Matter.
+
+Colophon
+--------
+
+A Halley's Comet Software production.
+
+Bug reports welcome!
+
+Git: https://github.com/hcs64/neon64v2
+Forum: https://hcs64.com/mboard/forum.php
+Email: [email protected] 
+
+-hcs 2020-07-07

plans.txt

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+Architecture ideas:
+- Data layout should be more intentional, to understand how things
+  are colliding, e.g.:
+  * Jump tables shouldn't be embedded in code, or should be organized
+    as jumps instead of addresses (as in the opcode table).
+  * The most important things could be in memory that never gets evicted
+    (besides the register file). The biggest issue is dealing with the
+    random access pattern of the NES ROM. It might be possible to spread
+    that out to leave gaps in physical address space.
+- Rework the scheduler so the CPU can run more than 1 instruction ahead,
+  without having to yield constantly to allow other tasks to set interrupts.
+- dlists should be generated on the RSP to send to the RDP. This will
+  make some mid-frame effects easier.
+- If I want expansion audio, the RSP scheduler needs to swap ucode, and/or
+  I have to optimize for space.
+- Text rendering should use the RSP+RDP rather than uncached writes
+  on the CPU.
+
+Missing features needed for better accuracy:
+- Mid-frame palette changes
+- Mid-scanline BG changes (MMC2, fine X scroll change, etc)
+- BG-accurate SP0 hit
+- Bug-accurate Sprite overflow
+- Read of PPU activity
+- Audio IRQs (frame counter, DMC)
+- Palette deemphasis, greyscale
+- Proper screen size for PAL
+- Video signal parameters (slightly too narrow? starts too late?)
+
+Desired features:
+- Gameshark version
+- Controller 2
+- 4 player via Four Score
+- PAL NES mode switch at runtime
+- Proper text and profiling in PAL mode
+- Remember PAL setting per-game
+- Control remapping
+- Arkanoid paddle
+- Zapper
+- Reset, power cycle
+- PAL N64 mode
+- Unofficial CPU opcodes
+- Screenshots
+- Famicom Disk System
+- More mappers
+- NSF player (with mapper 31 this is pretty close)
+- Save to Controller Pak
+- Savestate (Expansion Pak, persistent)
+- Unlock framerate, fast-forward
+- Some NES 2.0 support?
+
+Desired mappers:
+Easy
+- 34 (Deadly Towers)
+- 11 (Color Dreams)
+- 66 (SMB+Duck Hunt)
+
+- 111 (homebrew, memblers)
+
+- 5 (MMC5, Castlevania 3, etc)
+- 9 (MMC2, Punch-Out!!)
+- 10 (MMC4, Fire Emblem, etc)
+- 19 (Namco 129/163, Pac-Man Championship Edition, etc)
+- 24 (VRC6a, Akumajou Densetsu)
+- 25 (VRC6b, Madara etc)
+- 64 (Tengen Rambo-1)
+- 68 (After Burner)
+- 69 (Sunsoft FME-7, Gimmick!, etc)
+
+Known bugs:
+- Streemerz uses a bad opcode (by design) after Faux logo
+- Bill & Ted palette messes up when dialog boxes come up. - Needs mid-frame palette change (also Wizards & Warriors)
+- Battletoads intro: a line of bad scroll (?) under the logo, during the quick
+  pan the planet sometimes flashes into the upper screen (check hw?)
+- Rad Racer - single lines out of place (check hw?)
+- Jurassic Park - Ocean logo on the title screen seems to have a few lines out of place (check hw?)
+- Pop when shooting sword in Zelda is irritatingly loud
+- Some audio glitching in Mega Man 2 intro (check hw?)
+- Black line over Kirby in pause screen - This is going to require better IRQ timing and maybe mid-scanline scroll
+- Marble Madness garbled text - Needs mid-scanline pattern addr switch.
+- Big Nose Freaks Out doesn't get in-game. Needs IRQ?