stm32f_GBCart

##How to build project:

1. mkdir Gameboy
2. cd Gameboy
3. git clone https://github.com/dwaq/stm32f_GBCart.git
4. cd stm32f_GBCart
5. Download STSW-STM32068 from http://www.st.com/web/en/catalog/tools/PF257904# and then cd to its directory
6. unzip stsw-stm32068.zip -d ~/Gameboy/
7. cd ~/Gameboy/stm32f_GBCart/linker
8. ./get_and_modify_linker.sh
9. move your Gameboy rom into ~/Gameboy/stm32f_GBCart/roms
10. cd ~/Gameboy/stm32f_GBCart/roms
11. ./create_rom.sh filename.gb
12. cd ..
13. make

##How to program board (Linux): There's lots of ways to do this (just google it), but the way I prefer (from http://vedder.se/2012/07/get-started-with-stm32f4-on-ubuntu-linux/) is below (others may require additional steps because my system has many packages installed from previous prjects I've worked on):

1. Install QStlink2 (https://github.com/fpoussin/qstlink2) from source or linked package
2. run ```qstlink2'''
3. connect your board to the PC
4. click "Send..."
5. open ~/Gameboy/stm32f_GBCart/gbcart.bin
6. Confirm Yes

Game Boy Cartridge emulation from a stm32f4 Development Board

I wrote about this project in my blog:

• https://dhole.github.io/post/gameboy_cartridge_emu_1/
• https://dhole.github.io/post/gameboy_cartridge_emu_2/
• https://dhole.github.io/post/gameboy_custom_logo/

Description

This project implements the emulation of a gameboy cartridge using a stm32f4 Development Board. A real gameboy can be connected to a stm32f4 running this software and load real roms as well as homebrew roms.

• ROM Only and MBC1 Cartridges are implemented. See a full list at:
  • http://www.devrs.com/gb/files/gbmbcsiz.txt
• RAM emulation implemented. The contents will be erased upon powering off the stm32f4
• Custom boot logo implemented. It will be shown only during the first boot.

ROMs

In order to use a rom in the code, the file must be converted into a C array:

cp Tetris.gb rom.gb
xxd -i rom.gb | sed 's/unsigned/unsigned const/g' > tetris_rom.h
rm rom.gb

Files

main.c: Main Program body.

Initialization of the GPIOs.

stm32f4xx_it.c: Interrupt handlers.

The interrupt handler for the rising flag trigger is defined here. It handles the read and write operations of the gameboy to the cartridge.

Custom logo

draw_logo.py: Draws a logo on a window

Requieres pygame

make_logo.py: Converts a png logo image into a binary file to be used as a boot logo

Requieres pygame

./make_logo.py dhole_logo2.png dhole_logo2.bin
cp dhole_logo2.bin logo.bin
xxd -i logo.bin > dhole2_logo.h
rm logo.bin