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Simulation project for a SNK NeoGeo hardware definition. This does not go in a FPGA yet :)

This is being made possible by neogeodev contributors and Patreon donators: Alexis Bezverkhyy, Alexis Huet, Ange Albertini, Artemio Urbina, Arthur Lemoine, Blastar, Charly, Cyrille Jouineau, Jonathan Bayle, Laurent Lieben, Lewis Waddington, Mahen, Marshall H. (Retroactive), Maxime Mouflard, Valérianne Lagrange, ....


Green is what this project is all about. Yellow is simulation/testbench files. Grey are results from simulation.

ROM initialization files aren't provided for obvious reasons. You can get them from any ROM download website and convert them with tools/rom2verilog.c. I'm mostly using mslug (Metal Slug I) for now since it uses lots of moving sprites.

The system's top file is neogeo.v, currently used testbench is testbench_1.v .

Take a look in LSPC2RE and B1RE for porn (main video chips internal schematics). This was made possible by tracing die pictures provided by John McMaster.


Part Progress Notes
CPUs 100% Using 68000 and Z80 open cores for now, wrappers are working
IRQs 90% Logic is there, timer IRQ needs precise testing
ROMs 100% System ROM, S1, M1 and L0 are working
RAMs 100% Work RAM, Backup RAM, VRAM and memory card are working
I/O 95% No RTC for now
Video 100% LSPC and NEO-B1 video chips are fully tested and working
Audio 5% Lots of work needed on YM2610, no audio output at all for now

Cartridge model (MVS for now)

  • mvs_cart.v : Just wires both CHA and PROG boards into a cartridge model
  • prog_board.v : MVS cartridge model PROG board (V ROMs, P ROM)
  • rom_p1.v : 68k program ROM
  • rom_v1.v : Sound ROM
  • rom_v2.v : Sound ROM
  • cha_board.v : MVS cartridge model CHA board (C ROMs, S ROM, M ROM)
  • rom_c1.v : Sprite graphics ROM
  • rom_c2.v : Sprite graphics ROM
  • rom_s1.v : Fix graphics ROM
  • rom_m1.v : Z80 program ROM
  • neo_273.v : SNK latch chip
  • zmc.v : Z80 Memory Controller (can be part of ZMC2)

External memory

  • memcard.v : Memory card
  • rom_l0.v : Shrink lookup table (L0) ROM
  • rom_sp.v : System program (SP-S2 BIOS) ROM
  • rom_sfix.v : Embeded fix graphics (SFIX) ROM

NeoGeo model

  • cpu_68k.v : Wrapper for TG68K
  • tg68k.vhd : TG68K Motorola 68000 CPU core (VHDL)
  • cpu_z80.v : Wrapper for TVZ80
  • tv80_core.v : TV80 Z80 CPU core
  • neo_c1.v : SNK address decoding, joypad inputs, system maestro chip
  • c1_regs.v : On-chip registers
  • c1_wait.v : Wait state generator
  • c1_inputs.v : Player inputs
  • neo_d0.v : SNK memory card, clock and joypad outputs chip
  • clocks.v : Clock divider
  • z80ctrl.v : Z80 controller
  • neo_e0.v : SNK memory card I/O chip
  • neo_f0.v : SNK MVS cab I/O chip
  • neo_i0.v : SNK MVS cab I/O chip
  • syslatch.v : System latch/register
  • lspc_a2.v : Where the magic lives
  • resetp.v : Reset pulse generator
  • irq.v : 68000 IRQ gen/ack
  • videosync.v : Video sync and "ticks" generator
  • slow_cycle.v : Slow VRAM access sequencer
  • vram_slow_l.v : Slow VRAM chip LSBs
  • vram_slow_u.v : Slow VRAM chip MSBs
  • fast_cycle.v : Fast VRAM access sequencer
  • vram_fast_l.v : Fast VRAM chip LSBs
  • vram_fast_u.v : Fast VRAM chip MSBs
  • p_cycle.v : P bus sequencer
  • autoanim.v : Auto-animation specifics
  • hshrink.v : Sprite horizontal shrink logic
  • neo_b1.v : SNK graphics buffer chip
  • watchdog.v : Watchdog timer part
  • linebuffer.v : Pixel line buffers (x4)
  • m68kram.v : 68k work RAM helper
  • ram68k_l.v : 68k work RAM LSBs
  • ram68k_u.v : 68k work RAM MSBs
  • zram.v : Z80 work RAM
  • palram.v : Palette RAM helper
  • palram_l.v : Palette RAM LSBs
  • palram_u.v : Palette RAM MSBs
  • sram.v : Backup RAM (MVS) helper
  • sram_l.v : Backup RAM LSBs
  • sram_u.v : Backup RAM MSBs
  • ym2610.v : Yamaha YM2610 sound chip
  • ym_timer.v : Timer and IRQ part
  • ym_ssg.v : Simple Sound Generator part
  • ssg_ch.v : SSG channel
  • ym_pcma.v : ADPCM-A voices part
  • ym_pcmb.v : ADPCM-B voice part
  • upd4990.v : NEC uPD4990 interface to some modern RTC chip
  • neo_zmc2.v : SNK graphics chip (most of it done by Kyuusaku)
  • zmc2_dot.v : Graphics serializer part
  • videout.v : Video output latch
  • ser_video.v : Video serial interface
  • ym2i2s.v : Sound serial interface


Simulation only cartridge NeoGeo hardware definition








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