JEG Emulation Gathering

The main goal is to build a NES emulator with developers as target audience. Porting the emulator to various embedded platforms is made possible by having a clean abstraction of hardware dependent components. Whether your need is to have hundreds of instances running in parallel or replace audio and video components for experiments - JEG will be your friend.

Features

• Platform independent
• Cycle catch-up emulator design
• Plain C (C99) implementation
• Unit tested

What's working

• CPU 6502 completed
• PPU nearly completed (ppu_vbl_nmi timing test is failing)
• APU missing
• Cartridge abstraction draft is working
• Supported Mappers: INES #0
• Prototype UI using SDL library (for graphics and audio)

Usefull projects during developlemt

• github:fogleman/nes (Go, pixel based rendering)
• github:NJUOS/LiteNES (C, scanline based rendering)
• github:amhndu/SimpleNES (C++, pixel based rendering)

Test ROMs

Just call make test do run all tests. Taken from NESDev and github:christopherpow/nes-test-roms.

Valid

• Klaus2m5/6502_65C02_functional_tests by Klaus Dormann
• blargg_ppu_tests_2005.09.15b (without power up test) by Shay "blargg" Green
• branch_timing_tests by Shay "blargg" Green
• cpu_dummy_reads by Shay "blargg" Green
• cpu_exec_space(without apu) by Shay "blargg" Green and Joel "bisqwit" Yliluoma
• cpu_timing_test6 (without unofficial) by Shay "blargg" Green

Not working (yet)

These tests are also not called by make test.

• blargg_nes_cpu_test5 by Shay "blargg" Green - Mapper 1 not supported yet
• cpu_dummy_writes by Joel "bisqwit" Yliluoma - ROM should be not writeable
• cpu_reset by Shay "blargg" Green - no soft reset available yet
• ppu_vbl_nmi by Shay "blargg" Green - would be really nice...

Thanks

• GorgonMeducer doing the EmbeddedNES-Project for discussing a lot of optimisation patterns, sharing his know how and bring in usefull code!