MIDI Out

Yay, I found a way to up the FPGA area usage to 99.3% 🙂

UARTs are cheap in terms of resource usage. They can be hand-optimized to use less than 20 LUTs and FFs. However, when the FPGA is close to full, synthesis times skyrocket. That makes anything definitely not cheap in engineering time. If for anything though, that’s what quarantines are good for!

So I implanted a new UART and got MIDI out in XFM2 implemented. Because it’s essentially a UI-less module, it doesn’t do much. But what it does can be interesting for builders or users who want to know the parameter status using MIDI system exclusive messages (this was already implemented using high-speed standard RS-232).

In order to generalize the sysex command functionality (and get it outside parameter space) some sysex commands have been changed in this build. The updated ones are:

Initialize Program
F0 43 uu 04 00 00 00 F7

Write Program
F0 43 uu 04 01 nn nn F7

Read Program
F0 43 uu 04 02 nn nn F7

Then, the new parameters which use the MIDI out, are:

Get Parameter Value
F0 43 uu 04 03 nn nn F7

Get Program Dump (512 parameter values)
F0 43 uu 04 04 00 00 F7

Where uu = unit number, and nn = relevant parameter in each case.

The MIDI out connection requires just one resistor:

I’ll drop the beta binary in the next blog entry as it has one more goodie.