This add-on board lets you play OPL, OPL2, and OPL3 VGM files using your MegaGRRL Desktop.
This board is provided as an experimental add-on. Software support is working, but incomplete. Software support may improve in the future.
MegaGRRL Desktop Firmware v0.97dev or newer is required! See Firmware Releases
- Power off the MegaGRRL Desktop.
- Remove the YM2612 and SN76489, and seat the addon board into their sockets.
- Set all 4 DIP switches on the desktop board to OFF.
- Power on. The presence of the OPL3 board will be detected upon boot. Play an OPL/OPL2/OPL3 VGM file.
| Ref.Dsg. | Value |
|---|---|
| C1 | 10uF electrolytic |
| C2 | 47pF ceramic |
| C3 | 2.7nF ceramic |
| C4 | 2.7nF ceramic |
| C5 | 0.1uF ceramic |
| C6 | 0.1uF ceramic |
| C7 | 0.1uF ceramic |
| R1 | 33 ohm |
| R2 | 1k ohm |
| IC1 | YMF262 aka YMF262-M (SMD) |
| IC2 | YAC512 (SMD) |
| IC3 | TL072 (THT) (or SA5532, many opamps will work) |
| D1 | 1N5819 |
| Misc | 0.1" machine pin male-to-male headers, 40 pins total required. Must be machine pin type!!! |
All capacitors, resistors, diode are THT
- Solder on the SMD components (YMF262, YAC512)
- Solder on the THT components (SA5532, capacitors, resistors, diode)
- Solder on the pin headers (use MegaGRRL Desktop IC sockets for alignment)
Gerbers for JLCPCB are in the gerbers/ directory.