Midi to CV in Eurorack or as standalone
Set on hold - MK2 is in progress ATM
Stage | Detail | Status |
---|---|---|
create material | sch/pcb | produced Rev A |
gerber | produced and uploaded RevA | |
production | ordered | OK |
produced | OK | |
delivered | OK | |
------------- | ------------- | ------------- |
SOFTWARE | LFO | OK |
SOFTWARE | MIDI MAP | OK - Stage 1 |
SOFTWARE | CV | Ongoing |
Test | Detail | Status |
---|---|---|
Initial Inspection | Visual - Component Mounting | NOT OK |
Initial Technical Test | Base operation | MIDI OUT NOT OK |
Knobs | OK | |
Initial Technical Test | MIDI IN | OK |
Initial Technical Test | MIDI OUT | OK (to USB adapter) |
Initial Product Test | MIDI IN/OUT MAPPER | OK |
Initial Product Test | MIDI IN / CV OUT / GATE OUT | OK |
Initial Product Test | LFO OUT | OK (use different pinout) |
Test | Detail | Status |
---|---|---|
Product Test | MIDI IN/OUT | OUT - FAIL on Roland keyboard |
Product Test | LFO on DIO6 and 9 with ext RC | OK ! |
Quality | LFO | Very usable |
Quality | MIDI IN | |
Quality | MIDI to CV | |
Quality | MIDI to GATE | |
Long Term Product Test | MIDI IN | |
Long Term Product Test | CV OUT | |
Long Term Product Test | GATE OUT | |
Long Term Product Test | LFO OUT | OK |
Please note that the PIN1 and PIN2 are GATE. This is note described clearly in http://www.doepfer.de/a100_man/a100t_e.htm and needs to be noted when soldering the IDC header or when cabling if a Pin header has been mounted.
- The two pots on the breakout board are too close for adding a knob
- The orientation of the pinheader for the MCP4725 module - if mounted incorrectly the magic smoke disappears
- 0R could be replaced with SMD jumpers
- Consider a 200 mA fuse for Vin and 50mA for +5V pwr
- The mounting hole that is off center is not matching both boards
- Footprint of PJ-321 has too small drill holes (1mm) - major
- Footprint of PJ-321 is too narrow in the rear end :) - minor issue
- Midi out circuit is WRONG - Major
- Midi out not working - PCB workaround mod partially possible for voltage controlled inputs.
- --Remove GND around DIN pin 5 (bottom copper side)
- --Cut GND track to DIN pin 5 (top copper side)
- --Remove Q1, R6, R9
- --Connect 220R THT to base pad on Q1
- --Connect C and E on Q1
- --Add GND wire to pin2 of MIDI out DIN
- 100x100mm
- Separate unit with no alteration
- Optional split in 2 for eurorack mount mirrored config
- Arduino Nano - where the magic lives (remember to socket it to be able to reprogram it)
- Jack connectors: PJ-321 (important for the footprint)
- KY-40 Encoder module (important for the pullup, footprint and 3D alignment)
- MCP4825 module - if chosen (important for CV out function - footprint needs to match) If these are chosen the last two CV jacks should be ommitted.
- MCP4728 chip - if chosen (important for the last 2 CV out)
The board can be used as is for a prototype development of MIDI to CV
The board can be devided in two and combined front to front with spacers for a MIDI to CV eurorack module.
If only MIDI features are required the base board can work without the IO section.
The main board (with the arduino) has a couple of headers that can be connected to a different interface board using I2C, Analogue Inputs and Digital I/O.
The MIDI components can be omitted if the features does not require MIDI, like an LFO, VCO or ADSR circuit.
Arduino Nano based Controller and MIDI decoder.
MIDI In through a PC814 (or optional PC817) Optocoupler and into the RX pin on the Arduino
Optional expansion
Gate pins from Arduino
I2C Dac with 2 options
2x MCP4725 DAC
1x MCP4728