macsaif

CV outputs in MBNG

6 posts in this topic

I am starting my next project, which is a patchable Model D clone controlled by CVs. I am adding extra LFOs controlled by CV. Totally I will need 48 8bit and 7 12bit CV, scan 48pots and 70 buttons in matrix, drive 250 leds, 50 direct outputs. Also I want to connect 4x20 character OLED display. I assume that for that number of IO I will need 2 NG boards. Is it possible to send MIDI CC parameters where 2 CC channels are merged and allowing of sending 8bit values? 

The chassis is in progress. 

Frank

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12 hours ago, macsaif said:

Is it possible to send MIDI CC parameters where 2 CC channels are merged and allowing of sending 8bit values? 

When you say "2 CC channels" you want to say 2 CC numbers?
MIDI can't transmit 8 bit value, max is 7bit except if you use two CC, one for MSB(Most significant bits) and another for the LSB(Less significant bits), which will give you 14bit resolution max.The Pitch Bend is already a 14bit parameter, but it's not CC it's PB MIDI status.
Best is to keep the resolution from your Pots(assuming they are 12bits ADC) to your DAC internally, and get less resolution(7bits) from external MIDI control.

Best

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The CC outputs will be connected to ElectricDruid chips which have 8 bit input resolution and I want to use the whole range. Of course I do not need to solve this problem if I can connect 56 analog outputs to NG board but I think it is only 32/NG board, than I have to use another NG board and the remaining AOUTs will be connected to that board. There is possible to communicate via MIDI. If there is any solution to transfer 8 bit signal via MIDI this can be a solution (MSB+LSB).

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In that case I've got a solution for you but it's not ready for the moment.

In regular MIDI(UART) if the byte is >127 it is always recognised as a status byte, less it's always data. But the MCAN is not an asynchronous link, and each packet has is own header, like in an ethernet frame, then it's possible to transmit a status followed by some 8bit data, it's the position of the byte in the frame which determines what it is.
I will try to find some time to finish it, @Zam needs it for his project. @monokinetic also has a secret project around it.

Best

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Hello

55 DA is a lot, as say MB_NG only support 32 AOUT (per core)

So far there is no MUX option for AOUT_NG.

AINSER scan is not a issue, we have the muxed version for 64 pot

So you need two core, which can be a good option, or even 3, two for data scanning and HW handling and one master for Midi IO and multicore dialling, MCAN connection between all :happy:

 

2 hours ago, macsaif said:

If there is any solution to transfer 8 bit signal via MIDI this can be a solution (MSB+LSB).

Midi offer 16384 control with 16384 steps (14bit)... we call this NRPN :decayed:

At NG side, I'll recommand to use NRPN data for all your "more than 7 bit" data, and just use map definition to scale to/from whatever bit deph or range you need.

 

Best

Zam

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1 hour ago, Zam said:

Midi offer 16384 control with 16384 steps (14bit)... we call this NRPN :decayed:

Right! I Forget it ;)

Edited by Antichambre

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