Moog Music Forum

I don't know if this has been covered here. I couldn't find any guidance, so I thought I'd share.

I just updated my Voyager from OS 3.3 to 3.5 using linux--ubuntu 10.04 to be exact. I followed the Moog provided instructions and used Simple Sysexxer to send the sysex files.

When I first tried, SS was sending faster than the Voyager could handle. I could tell because I kept getting a "System Exclusive transfer has failed!!!" message on the Voyager LCD, and I noticed the SS progress bar was way ahead of the Voyager's. SS is very barebones and doesn't have a configuration menu, so I downloaded the source code. I hadn't worked with any code on this PC yet, so I also had to install the following development libraries and tools: libasound2-dev, libqt4-dev, and g++. All I had to change was one line of code in MidiOut.cpp to slow the sending enough for the Voyager to keep up.

From: usleep( chunk.size() * 352 );
To: usleep( chunk.size() * 352 * 2 );

Then I compiled, and everything seems to have gone well.

When I first tried, SS was sending faster than the Voyager could handle.

Hi,
it is not possible to send MIDI data faster than the Voyager can handle. The Voyager handles MIDI data in realtime. I think the problem has to do with the MIDI interface or the MIDI drivers of the computer.
Have fun,
Rudi

Hmm, well certainly there must be some upper limit.

Nonetheless, my assessment that the Voyager couldn't keep up is based on the SS sending bar reaching 100% at the same time the Voyager receiving bar receiving bar showed about 70%, right before switching to the error message. And, of course, increasing the delay between sending chunks of sysex fixed the problem. The sending and receiving bars were more or less in sync after I increased the delay.

My sending path was SS -> jack -> Audiophile 2496 PCI -> Voyager over MIDI cable. I've never had a problem with the MIDI interface being slow, so I don't know what else to blame it on.

well certainly there must be some upper limit.

No, believe it (or maybe not) I made a lot of tests and when you would connect a second computer to receive the MIDI data of the Linux computer you would get also a wrong SysEx transfer.
I'm not a programmer for computer MIDI interfaces but I guess the problem has to do with an overrun of the buffer in the MIDI interface.
Have fun,
Rudi