MIDI sequencers are surprisingly expensive, making them an excellent target for [RH Electronics] who has created a sixteen-step device. It supports up to eight playable parts per step, which can be either MIDI or drum triggers.
The case and front panel are built to a very high standard, and on a piece of stripboard within lies an ATmega644 which does all the MIDI work, an ATmega328 that runs the many LEDs, and an ATtiny85 that reads the front panel buttons. The whole is kept in sync by a timer on the 644 set to produce the required MIDI clock. There is an LCD display too, which carries the status and programming interface.
You can see the result in the video below the break, in which the sequencer is put through its paces alongside a tantalising glimpse of a matching synthesiser. Is this another project, or a commercial device on which Google fails us when we try to find it? Meanwhile this is certainly not the first MIDI sequencer we’ve brought you here at Hackaday, this Arduino one is another example of several also using Atmel parts.
I used to think, “I could do that with one microcontroller.” But since microcontrollers are cheaper than the chips it takes to expand their I/O ports, this approach is seeming better and better. This finally got through my head with the HaD article about hacking a replacement for a top-octave synthesizer chip. (https://hackaday.com/2018/05/24/ask-hackaday-diy-top-octave-generator/) There were lots of ways to do the job with a few chips, but no convincing strategy for implementing such an asynchronous application on a single 8-bit uC.
There’s good news and bad news for multi-controller systems, though: the good news is, each uC can be very compartmentalized, so that when you need to do an update, you only have to update the one that had a problem. The bad news is, if you need to update a chip, you have to make sure you’re updating the RIGHT chip!
I’m still of the mind that as few programmable devices should be used as possible. Software management and debugging times increase with the more programmable devices you add. it’s all easy until you run into some weird issue with the inter processor communications links or a weird timing issue that happens only once in a blue moon.
Just looking at the lead image of the video, those knobs on the synthesizer, look to be “speed knobs” that are normally used on a Les Paul style guitar. So, I’m thinking it is another project.
Restricted 8 or 16 step sequencers are ten a penny.. How is it that 15 year old hardware sequencers run rings around all this junk?.. Better polyphony, more tracks, ability to support cc, nrpn and sysex, arpegiator and chord modes… Ffs these developers need to stop mailing it in and create a sequencer that is musically useful beyond the blip blop fart brigade…
I 100% agree with BackinTday… But that’s why I’m here, to figure out how to create the sequencer I want.