8-bit Emulator Programming with Go

Introduction to emulator programming including source code of a Game Boy emulator written in Go: https://github.com/drhelius/demo-emulator

This was presented at Codemotion 2016 (Madrid, Spain): https://2016.codemotion.es

Transcript

1. golang emus Ignacio Sánchez Ginés @drhelius
2. Emulator = legal ROM = ilegal
3. Emulator ≠ Simulator
4. Interpreter LD A,(HL) SUB 1 JR C,CONTINUE CP B JR NZ,LOOP Decode Read Exec
5. Binary Translation Target Machine Code LD A,(HL) SUB 1 JR C,CONTINUE CP B JR NZ,LOOP
6. Dynamic Recompilation Trans Read Exec LD A,(HL) SUB 1 JR C,CONTINUE CP B JR NZ,LOOP Target Machine Code
7. CPU MEM IO Audio Video Input
8. CPU 6502 Z80 Game Boy * Master System Game Gear MSX ZX Spectrum NES Atari 2600 Commodore 64 Apple 2 Super NES 65816
9. CPU MEM 8-bit 16-bit
10. 0000 FFFF 0 65535 16KB 16KB 16KB 16KB
11. 8DC4F3CD 293D2144 FF3E92BE 20FDCD0C ........ parameter opcode opcode opcode parameter
12. Main Loop while true { updateCPU() updateVideo() updateInput() updateAudio() }
13. updateCPU() { opcode = fetchOpcode() runOpcode(opcode) }
14. 100 clks N clks CPU Video Input
15. CPU 4 MHz MEM Timer Audio Video Input Cart Game Boy
16. CPU H L B C D E SP PC A F 16 bit 8 bit
17. Flags 0 0 H C 0 0 Z N 1 0 5 4 3 2 7 6
18. 16 KB ROM Bank 0 16 KB switchable ROM bank 8 KB Video RAM 8 KB switchable RAM bank 8 KB internal RAM Mirror 8 KB internal RAM Sprite Memory (OAM) Empty IO Ports Empty Internal RAM Interrupt Register cartridge FF4C FF80 FEA0 FF00 FFFF FE00 E000 C000 A000 8000 4000 0000 cartridge
19. j j+1 X N i+1 i 2 1
20. 16 KB ROM Bank 0 16 KB switchable ROM bank 8000 4000 0000
21. Bank 0 Bank 1 Bank 2 Bank 3 Bank 4 ... fixed 00000 04000 08000 0C000 10000 14000 switchable Bank 4
22. ROM RAM MBC
24. Visible 160x144 HBlank VBlank 1.08 ms 48.6 us
25. Demo Emulator main core glfw opengl cpu video input
26. Workshop go get -u github.com/drhelius/demo-emulator cd $GOPATH/src/github.com/drhelius go run main.go -rom workshop.rom