OK, the trigger-to-MIDI clock converter seems relatively happy (though I think the MIDI in on my AN200 isn’t? That’s going to require some more tests…).<\/p>\n
I hacked on it a bit tonight trying to determine how drifty the generated MIDI clock was relative to the incoming trigger pulses from the DR-110.\u00c2\u00a0 At first it was pretty ugly. I then added some compensation to the clocking to account for all of the work the Arduino is doing. After some trial-and-error, it’s relatively tight – total drift by my rough calculations was something like 10 milliseconds over a five minute period. Compare that to an earlier drift of 120 ms in a minute…<\/p>\n
Here’s the code: trigger2midisync.pde<\/a><\/p>\n Hardware-wise, there’s a trigger input on pin 2 (use a zener if you’re worried about blowing stuff up…), and the MIDI out is the standard (TX, GND, and 5V through a 220 ohm resistor going to the pins of the MIDI port).<\/p>\n You may want to configure some of the #define statements in the code. STOP_TIMEOUT is the amount of time that needed without triggers needed for the converter to decide to stop. I’m using 2 seconds.\u00c2\u00a0 Changing DIVIDE_SLICE would be important if your trigger source is something other than 4ppqn, and CODE_OVERHEAD_TIME is used to adjust drift in your deployment – 10 worked really well for me in my tests tonight, but it could be anything for others.<\/p>\n Once it’s hooked up and connected to your MIDI source and your trigger source, start sending a series of pulses to pin 2. On the first pulse, MIDI Clock start should get sent, and by the third pulse or so the sync will be “synced” – there will be an offset, but it should remain fairly constant. Now, once the pulses stop, clock will continue to be sent until STOP_TIMEOUT milliseconds have passed.<\/p>\n Next test will be syncing the DR-110 to the very-nearly-finished x0xb0x to see how well that keeps up – I did all my tests tonight with a Yamaha RY10, with both it and the DR110 just playing a “four on the floor” kick pattern.<\/p>\n Questions? Comments? Improvements?<\/p>\n","protected":false},"excerpt":{"rendered":" OK, the trigger-to-MIDI clock converter seems relatively happy (though I think the MIDI in on my AN200 isn’t? That’s going to require some more tests…). I hacked on it a bit tonight trying to determine how drifty the generated MIDI clock was relative to the incoming trigger pulses from the… Continue reading