Boy

Boy is a Gamboy (dmg not 0) emulator written in Java.

Goals

• Writing a good understandable emulator without any magic
• Understanding how the hardware works to make a clear implementation

Non-goals

• Having the best performance

To-do

• Pass all tests for dmg (not 0)
• Implement sound
• Make implementation of MBC1 clearer
• Implement all other MBC's

Tests

Blargg's cpu_instrs tests

Test	Boy
01-special	👍
02-interrupts	👍
03-op sp,hl	👍
04-op r,imm	👍
05-op rp	👍
06-ld r,r	👍
07-jr,jp,call,ret,rst	👍
08-misc instrs	👍
09-op r,r	👍
10-bit ops	👍
11-op a,(hl)	👍

Blargg's instr_timing tests

Test	Boy
instr_timing	👍

Blargg's mem_timing tests

Test	Boy
01-read_timing	👍
02-write_timing	👍
03-modify_timing	👍

Mooneye GB acceptance tests

Test	Boy
add sp e timing	👍
boot div dmgABCmgb	❌
boot hwio dmgABCmgb	👍
boot regs dmgABC	👍
call timing	👍
call timing2	👍
call cc_timing	👍
call cc_timing2	👍
di timing GS	👍
div timing	👍
ei sequence	👍
ei timing	👍
halt ime0 ei	👍
halt ime0 nointr_timing	👍
halt ime1 timing	👍
halt ime1 timing2 GS	👍
if ie registers	👍
intr timing	👍
jp timing	👍
jp cc timing	👍
ld hl sp e timing	👍
oam dma_restart	👍
oam dma start	👍
oam dma timing	👍
pop timing	👍
push timing	👍
rapid di ei	👍
ret timing	👍
ret cc timing	👍
reti timing	👍
reti intr timing	👍
rst timing	👍

Bits (unusable bits in memory and registers)

Test	Boy
mem oam	👍
reg f	👍
unused_hwio GS	👍

Instructions

Test	Boy
daa	👍

Interrupt handling

Test	Boy
ie push	👍

OAM DMA

Test	Boy
basic	👍
reg_read	👍
sources dmgABCmgbS	❌

PPU

Test	Boy
hblank ly scx timing GS	❌
intr 1 2 timing GS	👍
intr 2 0 timing	👍
intr 2 mode0 timing	👍
intr 2 mode3 timing	👍
intr 2 oam ok timing	👍
intr 2 mode0 timing sprites	❌
lcdon timing dmgABCmgbS	👍
lcdon write timing GS	👍
stat irq blocking	❌
stat lyc onoff	❌
vblank stat intr GS	👍

Serial

Test	Boy
boot sclk align dmgABCmgb	❌

Timer

Test	Boy
div write	👍
rapid toggle	👍
tim00 div trigger	👍
tim00	👍
tim01 div trigger	👍
tim01	👍
tim10 div trigger	👍
tim10	👍
tim11 div trigger	👍
tim11	👍
tima reload	👍
tima write reloading	❌
tma write reloading	❌

Mooneye GB emulator-only tests

MBC1

Test	Boy
bits ram en	👍
rom 512Kb	👍
rom 1Mb	👍
rom 2Mb	👍
rom 4Mb	👍
rom 8Mb	👍
rom 16Mb	👍
ram 64Kb	👍
ram 256Kb	👍
multicart rom 8Mb	❌

Mooneye GB manual tests

Test	Boy
sprite priority	👍