P2 MIDI >>
Bob Lawrence (VE1RLL)
Posts: 1,720
in Propeller 2
@Ariba
Are you doing any midi work for the P2 yet? If not do you plan to?
Are you doing any midi work for the P2 yet? If not do you plan to?
Comments
MIDI out is easy; what I'm hoping to do in the long term is use the P2 as a synthesizer engine using from folks like Andy and Johannes.
I have a huge pile of midi instruments and controllers, including the tymkrs Protsynth midi (a P1 device). Would love a sound module made with the P2 using this board and Ahle2's reSound, and maybe some of the Protosynth stuff.
- MIDI in the form of a serial interface to other devices, like JonnyMac's board, is easy doable.
- USB MIDI would be possible, but needs a lot of USB driver knowledge, which I not have yet.
- A MIDI player, which plays samples or synth sounds from MIDI input is what I have plans for.
The P2 is the perfect chip for audio generation. Not only for digital sounds with the DSP instructions, also analog synthesis circuits can be easy controlled, with a DAC per pin. The good audio ADC and DAC quality allows things like Sampler and Looper or effect engines.
Andy
The audio synthesis part I don't know how to do yet, but it seems like creating a MIDI controller/sequencer with the P2 would be a breeze -- and a fun exercise to inspire others. That's why I made my little MIDI board.
Just generally speaking as to if you were making any P2 based designes, objects etc.
That sounds great.
As othere's have said that is a great looking board. What Opto-isolators are you using?
Did you incorperate any new ideas from the new MIDI 2.0 Spec's?
Some of you may not be aware of the new MIDI specification that came out recently. Here are a few links.
New MIDI 2.0 Specs
This article explaines some of the new features: "What will midi 2.0 mean for musicians?"
https://reverb.com/ca/news/what-will-midi-2-dot-0-mean-for-musicians?locale=en-CA
Download the new Spec's
https://www.midi.org/midi2
New MIDI Books:
I found 2 new books that will be out soon
https://www.amazon.com/MIDI-Manual-Practical-Production-Engineering/dp/0367549980/ref=sr_1_12?Adv-Srch-Books-Submit.x=25&Adv-Srch-Books-Submit.y=6&dchild=1&field-datemod=1&field-dateop=After&field-dateyear=2020&keywords=MIDI&qid=1597455794&refinements=p_28:MIDI&s=books&sr=1-12&unfiltered=1
The Musician's Guide to MIDI (The Musician's Guide to Home Recording)
https://www.amazon.com/Musicians-Guide-MIDI-Craig-Anderton/dp/1540024962/ref=sr_1_20?Adv-Srch-Books-Submit.x=25&Adv-Srch-Books-Submit.y=6&dchild=1&field-datemod=1&field-dateop=After&field-dateyear=2020&keywords=MIDI&qid=1597455957&refinements=p_28:MIDI&s=books&sr=1-20&unfiltered=1
I didn't. I have a couple of controllers and a really old keyboard so v1.0 is okay for now.
Info to be added over the weekend
Ok thank's . I found the data sheet and will have a look:
H11L1 Data Sheet:
https://www.mouser.ca/datasheet/2/308/FairchildSemiconductor_161483498766-1191905.pdf
Are you planning on inplementing a MIDI-object? Then I don't need to make my own wheel! Even though I believe that a little bit of "competition" makes for better wheels in the long run, I know that you are producing high quality code. (I have run most of your public stuff on the P1). So I will wait for what you put out and glue it together with my stuff.
I was floored when you made your "impossible" module player on the P1 using a SD card as a random access memory. Clever code!
MIDI 2.0 looks good. 256 channels, great! I grew up with Craig Anderton's articles. Still distilling MIDI.org full spec.
I did too. He had some great ideas.
Thanks, but the loops had problems, depending of where the loop points were located inside an SD sector.
I can't say when I will make such a 'wheel'. I did some experiments with the SoundFont (.SF2) format which contains samples and parameters for many instruments in one file.
You can find a lot of ready made SF2 files in the net, and also editors to make such files. The P2 needs a big RAM (HyperRam or PSRAM) to hold the whole file and plays the voices directly from this RAM.
I think I need my own P2 board with a lot of audio jacks, MIDI connectors, a big RAM and some sort of HMI.
Andy
The main SF2 I use on my PC is 148 MB. That's gonna be a big RAM
The Roland soundfont that comes with Windows (Usually only a DLS file, I have an SF2 version of it from somewhere) is not that terrible at 3MB.
I also have one that is only 1 MB and still sounds quite okay - if chooses a sensible subset, it could fit in hub easily.
Bigger SF2s have longer samples, and are often stereo. Single instruments sound better, but if you play a MIDI file, a small SF2 sounds often better.
If you make a custom memory board you might get nearer though. 2 x 64MB HyperFlash devices already get you to 128MB and my driver can support that config in theory, though its untested at that size given I only have the one P2 HyperRAM board to play with.
I imagine you could put 3-4 flash devices on a double wide breakout and still remain within 16 P2 pins if you share the clock/rwds lines instead of running them separately.
I'm only interested to know if there is a pure MIDI object in the making, not anything related to sound generation, SoundFonts or GM. General MIDI isn't that interesting to me, even though it would be cool to be able to playback GM files on the P2. I'm all about doing novel audio stuff on the P2, like virtual analog synthesis or experimenting with new kinds of synthesis. I may start coding on a pure MIDI object if nobody else has something in the works. I will definatley need it for my own stuff later on and it may be of interest to others that are doing "audio stuff" on the P2. It's not a priority at the moment though since I have promised Parallax to finish some other standard objects that they would like to have available when the P2 gets officially released.
Any recent MIDI developments?
-Craig
I have this midi board: https://www.sparkfun.com/products/12898
This file : https://github.com/pik33/P2-retromachine/blob/main/Propeller/Tracker player/retrocog.spin2 is the "universal input driver" - one of input processed in it is this midi port. This version receives data from midi, RPi Zero based kbm interface and Flexprop serial terminal.
Having up to 32 channel synthesizer and midi input makes it possible to write something that allows playing on a midi controller. This will be the next toy I want to write after I manage to make Prop2play running
@pik33
I see that they also have a BLE version.
Well I have spent a couple of days thinking and researching and I'm convinced that I have come up with an idea for a product that every performing musician needs and that doesn't already exist
Need to put my current killer project to bed first though
Craig
We were chatting here: https://forums.parallax.com/post/quote/174645/Comment_1540695
That we needed a couple of PS/2 ports as a P2 Accessory, and it was suggested that the other 4 pins be used for a MIDI port. This would provide the 2 types of common connections that aren't already provided for by existing accessories. MIKROE doesn't even provide a MIDI click, and their PS/2 click is pretty lame with just 1 port (uses 2 signals). @"Ken Gracey" & the rest, what do you think?