MegaGRRL - Portable YM2612 VGM Player

MegaGRRL is a project to make a portable device capable of playing back VGM files targeting the sound chips used in the Sega Mega Drive/Genesis and Master System. It uses the original chips and has a playback engine focused on accuracy and supporting as many features of the VGM file format as possible, all controlled by an ESP32 running FreeRTOS using the ESP-IDF framework.

Demo video: https://www.youtube.com/watch?v=_Bkd4rAutqE (Thunder Force IV - Metal Squad)

Currently, the VGM playback core is functional and working well. I'm using a third-party library for some debug output on the LCD, but I've written a new driver that uses DMA, pending writing some UI drawing routines. The hardware is essentially complete, and prototype PCBs have been designed, ordered, and assembled. A design for a 3D-printed enclosure is also underway.

Details

Hardware

MCU: ESP32, specifically the ESP-WROOM-32 module
Sound chips: YM2612, SN76489
Storage: MicroSD
Clock generation: 2x LTC6904
Display: ILI9341 320x240
Volume control: DS1807S+
Headphone amp: TPA6111A2
IO expander: MCP23017
DC-DC: 2x LM2735
Battery charge: MCP73832

Project Logs

Collapse logs

DAC streams are under control
natalie • 10/23/2018 at 10:45 • 0 comments

Uploaded two more videos again. This time, using two tracks that make heavy use of the DAC stream control subset of the VGM specification. Enjoy! Links to the artists are in the video descriptions, so go check them out if you like FM synth metal stuff~
More videos
natalie • 10/20/2018 at 18:01 • 0 comments

I put a couple more videos on YouTube today: