nicetoknowmisc - gbaHD/GBAHD-Shield GitHub Wiki

SD Card Update:

If you want to keep your device offline but still want to experience the latest and greatest features, you can simply add all Update files to SD Card. On the first boot afterwards, gbaHD will then copy these updates to its internal memory.

File	Update
esp32.bin	ESP32
spiffs.bin	ESP32 data partition
720p.bit	720P Bitstream
1080p.bit	1080P Bitstream

Buttoncombos:

The Shield performs its IGR by pressing: R | L | START | SELECT

The OSD combo is: UP | R | L | SELECT

Leaving the OSD: Start