diego dorado

CV-2612

CV2612 is an eurorack module based on the classic FM chip used by Sega Genesis: the great YM2612.
It has MIDI i/o, and yes! it has control voltage inputs!
It is on its final development stage and we hope to see it on the market soon.

MIDI Specs

CV2612 has two 3.5mm TRS MIDI connectors: MIDI In and MIDI Out. MIDI Out can act as a software MIDI Thru if THRU_ENABLE is 1.

Note Messages

Note On/Off messages are received on channels 1 to 7 If received on channel 1, they treated differently based on Poly Mode configuration

  • If Poly Mode is set to Mono, a note will use all six voices
  • If Poly Mode is set to Poly, a note will use a single voice with up to 6 voices of polyphony, first in/first out. Otherwise, notes on channels 2-7 goes to voices 1-6 respectively.

Pitch Bend Messages

Pitch Bend messages are received on channels 1 to 7 If received on channel 1, they affects all six voices Otherwise, pitch bends on channels 2-7 affects voices 1-6 respectively.

Received CC/NRPN Messages

CC messages received are on channels 1 to 16 Every CV2612 voice related parameter is mapped to a CC message by default according to the following table, but can be configured through the CV2612 Online Tool

MIDI DIN runs at 31250 bits per second. That’s roughly 3000 bytes per second, which in a MIDI stream transferring CC data (3 bytes each) as quickly as possible, works out to about 1000 CC changes per second.

play-mode vel-sensitivity cc-mode rgb-intensity

As a general rule, a parameter on MIDI channel 1 apllies to all six voices, and on Midi channel 2 to 7, applies to voices 1 to six respectively. Global parameters do not take into account the MIDI channel used.

NRPN MSB NRPN LSB CC Channel Code Parameter
Global Parameters
01 0 1 - LF0_F Low Frequency Oscillator Frequency
02 0 2 - LF0_E Low Frequency Oscillator Enable
03 0 3 - THRU_E Enable Software MIDI Thru
04 0 4 - TX_CC Transmit CC
05 0 5 - POLY_M Poly Mode (Mono/Poly)
Channel Parameters
20 0 20 1-7 AL Operators Algorithm
21 0 21 1-7 FB Feedback of Operator 1
22 0 22 1-7 FMS Frequency Modulation Sensitivity
23 0 23 1-7 AMS Amplitude Modulation Sensitivity
24 0 24 1-7 ST Stereo Configuration
Operator 1 Parameters
30 0 30 1-7 AR Attack Rate
31 0 31 1-7 D1 Decay 1 Rate
32 0 32 1-7 SL Sustain Level
33 0 33 1-7 D2 Decay 2 Rate
34 0 34 1-7 RR Release Rate
35 0 35 1-7 TL Total Level
36 0 36 1-7 MUL Frequency Multiplier
37 0 37 1-7 DET Detune
38 0 38 1-7 RS Rate Scaling
39 0 39 1-7 AM Amplitude Modulation Enable
Operator 2 …
1 40 1-7 AR Attack Rate
Operator 3 …
2 50 1-7 AR Attack Rate
Operator 4 …
3 60 1-7 AR Attack Rate
* Commands *
64 0 - - - Set a patch
64 1 - - - Select a patch

Transmitted CC Messages

A few CC messages are transmitted on channels 1 if TX_CC is 1 .

CC Channel Code Parameter
1 1 CV_MSB Control Voltage MSB
2 1 CV_LSB Control Voltage LSB
3 1 GATE Gate
- -
10 1 X_MSB X MSB
11 1 X_LSB X LSB
12 1 Y_MSB Y MSB
13 1 Y_LSB Y LSB
14 1 Z_MSB Z MSB
15 1 Z_LSB Z LSB

SysEx Messages

Other configuration parameters though, can only be changed with sysEx messages through the CV2612 Online Tool

As a brief description, the following sysex messages are received:

  • ID_REQUEST
  • PARAM_LOAD
  • MAPPINGDUMPREQUEST
  • MAPPING_LOAD
  • VOICEDUMPREQUEST
  • VOICE_LOAD
  • PATCHDUMPREQUEST
  • PATCH_LOAD
  • PATCHESDUMPREQUEST
  • PATCHES_LOAD

And the following sysex messages are transmitted:

  • ID_REPLY
  • MAPPINGDUMPREPLY
  • VOICEDUMPREPLY
  • PATCHDUMPREPLY
  • PATCHESDUMPREPLY

Being

  • ID: Identity of the device
  • PARAM: a single parameter
  • MAPPING: The CC to parameters mapping
  • VOICE: a single voice in the chip, a.k.a. channel
  • PATCH: a patch is comprised of 6 voices, lfo and ploymode settings
  • PATCHES: a set of 4 patches

Happy FMing!

banana

Beauty will be convulsive or will not be at all.
André Breton