Switch and Controller MIDI Foot Pedals
This unit converts up to 6 variable potentiometer and up to 5 switch
foot-pedals to an associated MIDI control signal. This unit will work with one,
two or up to all 11 inputs, at the same time.
The Switch and Controller MIDI Foot Pedal utilizes:
- An assembled, built and tested Arduino board including a
suitable pre-programmed Atmega168,
- A 2.1mm power socket, and associated LED,
- A MIDI activity LED,
- 6 inputs for variable potentiometer foot pedals,
- 5 inputs for switch type foot-pedals,
- A power-on LED,
- A 4-way DIP switch which selects the MIDI channel at power-on, see Table
3
- A 150mm wired MIDI 5-pin DIN input socket,
- A 150mm wired MIDI 5-pin DIN output socket,
- Switch and potentiometer Circuit
Schematic Diagram
The Switch and Controller MIDI Foot Pedal also requires:
MIDI IN/OUT Wiring:
Operation:
At power-on the DIP switch positions are read and the unit will operate in a
MIDI channel as shown in Table 3.
Circuit Schematic:
A circuit schematic of the
MIDI IN/OUT and Arduino shows the Input/Output connections. There is also a switch and potentiometer
Circuit
Schematic Diagram.
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Circuit Pin Wiring
Information |
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Jack Socket Wiring:
Switch foot pedals usually use a MONO jack socket. Variable
potentiometer pedals can use a MONO or STEREO jack socket.
So
either a
standard 6.3mm (¼in) style switched 2-pole
MONO jack socket with 2-poles switched upon insertion of the
jack plug, with switched normally closed contacts available
in 2-pole or
a
standard 6.3mm (¼in) style switched 3-pole
STEREO jack socket with 3-poles switched upon insertion of the
jack plug are required.
Power Supply:.
External power can come either from an AC-to-DC adapter
or battery. The adapter can be connected by plugging a 2.1mm center-positive
plug into the board's power jack. Leads from a battery can be inserted in the
Gnd and Vin pin headers of the POWER connector. A low dropout regulator provides
improved energy efficiency.
The board can operate on an external supply of 7 to 20 volts. If supplied
with less than 7V, however, the 5V pin may supply less than five volts and the
board may be unstable. If using more than 12V, the voltage regulator may
overheat and damage the board. The recommended range is 7 to 12 volts.
MIDI Pedal Switch Functions:
|
Switch Input Selections |
MIDI Pedal Functions |
| 1 |
Sustain |
| 2 |
Sostenuto |
| 3 |
Soft Pedal |
| 4 |
Legato |
| 5 |
Hold 2 |
|
Table 1 |
Sustain Pedal:
The sustain pedal is also known as the Damper Pedal. When operated it sends
out a controller value of CC64. When the pedal is pressed ON the unit outputs a
value of 127, when released OFF the unit outputs a value of 0. Tone-generators
without the 'half-damper' implemented will interpret a value between 0 and 63 as
OFF and a value of 64 to 127 as ON.
Sostenuto Pedal:
The sostenuto pedal is a type of selective sustain pedal found on acoustic
grand-pianos. Pressing down the pedal, sending controller value CC66 with a
value of 127, while holding notes on the keyboard will cause these notes to be
sustained after you release them. Any notes played after pressing the pedal will
not sustain. When the pedal is released it sends out controller value CC66 with
a value of 0.
Soft Pedal:
The soft pedal works in two simultaneous ways. When the pedal is pressed,
sending out controller value CC67 with a value of 127, the sound should be
slightly softened in terms of volume and there should be a noticeable difference
in the tone-colour of the sound. When the pedal is released it sends out
controller value CC67 with a value of 0.
Legato Pedal:
When the legato pedal is pressed, sending out controller value CC68 with a
value of 127, playing a different note changes the pitch of the current note
without re-triggering the attack phase of the envelope of the sound. When the
pedal is released it sends out controller value CC68 with a value of 0.
Hold 2 Pedal:
The hold 2 pedal is another type of sustaining pedal used fro sounds with two
sustain phases in their envelopes. When the pedal is pressed it sends out
controller value CC69 with a value of 127, when the pedal is released it sends
out controller value CC69 with a value of 0.
MIDI Pedal Controller Functions:
|
Controller Input Selections |
MIDI Pedal Functions |
| 1 |
Volume |
| 2 |
Modulation |
| 3 |
Foot controller |
| 4 |
Balance |
| 5 |
Pan |
| 6 |
Pitch |
|
Table 2 |
|
DIP Switch
Selections |
MIDI
Channel
|
| 4 |
3 |
2 |
1 |
| on |
on |
on |
on |
1 |
| on |
on |
on |
off |
2 |
| on |
on |
off |
on |
3 |
| on |
on |
off |
off |
4 |
| on |
off |
on |
on |
5 |
| on |
off |
on |
off |
6 |
| on |
off |
off |
on |
7 |
| on |
off |
off |
off |
8 |
| off |
on |
on |
on |
9 |
| off |
on |
on |
off |
10 |
| off |
on |
off |
on |
11 |
| off |
on |
off |
off |
12 |
| off |
off |
on |
on |
13 |
| off |
off |
on |
off |
14 |
| off |
off |
off |
on |
15 |
| off |
off |
off |
off |
16 |
|
Table 3 MIDI Channel |