First post, by LABS
- Rank
- Member
Hello there!
This is a new design I've been working on for quite some time.
OPi is an external USB sound device that allows games and other software running in DOSBox to use an original OPL3 chip for music playback. Additionally it has a line audio input for mixing PCM sound from a computer with OPL3 music and send it to a single line output of OPi. So when you play a DOSBox game - you hear everything from one output of the OPi (original OPL3 music + PCM sound) and both signals have separate volume controls. No need in external mixer. Thus, the device is also an external volume control for the computer's line out. The device is USB-powered. It requires USB 2.0 or better. USB 3.0 is faster (~15000 OPL3 packets per second vs ~6000 on USB 2), but at this moment only Descent feels the difference (as I remember it was also choking on P100+SB16 back in 1995) 😀
The project was started during countless lock-downs when it was impossible for me to access my old PC's, but a real OPL3 experience was needed 😀 Then it was on hold for some time due to the component shortage and now it is still in prototype state.
Here are some demos, but only showing OPL3 for now
OPL3 + PCM are upcoming 😀
These demos run a modified DOSBox, which uses OPi's programming interface.
Showing the OPi with Adlib Tracker (room sound):
https://youtu.be/0SPgaSzxr2o
A crazy OPL3 command stream (ISHTAR.A2M, line out sound):
https://youtu.be/FA_rSxOP99s
Also heavy stream (GLASS.A2M, line out sound):
https://youtu.be/eA1RuPGxlks
Actually the device is working fine, but it needs to become more mature and compatible. Currently lots of actions needed with the machine in order to prepare it for using the OPi. The device uses FTDI USB chip for communication with the host machine. So, an FTDI driver should be installed. A DLL with OPi API is already working - a DOSBox with OPi support uses it. At the moment it works only on Windows. The plans are to support Linux and macOS.
I'm open to any suggestions and ideas
I think that this is a compact and pretty idea and hope that maybe someone else could find it useful. If so - I will continue working on it, so it could be compatible with as much machines as possible, but only with mine 😉