A little bit of info re the I2C protocol and how it relates to midi and synths.
It's also called rather confusingly IIC or i2c or the I²C (Inter-Integrated Circuit) interface.
Anyway, it's a digital communication protocol and it looks like it's becoming more common in the synthesizer world.
Buchla used this back in 2005 when Don developed the 200e.
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He used this on the 200e's internal "power" bus (obviously it distributed more than just power):
Pin 8 = Yellow: i2c clock
Pin 9 = Green: i2c data
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This is how the modules talked to each other without the need of patch cables... how internal midi, preset management, clocks, etc were distributed within the 200e environment.
It appears that i2c uses just 2 "wires" to transmit the necessary data.
They are:
SDA (Serial Data) – The line for the master and slave to send and receive data.
SCL (Serial Clock) – The line that carries the clock signal.
Interestingly the Monome Aleph and the Teletype also use i2c.
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The Aleph ingeniously use a simple 3.5mm stereo jack. It's just labeled "ii"
According to their website:
" the bus is addressable (multiple devices on a chain), fast (400k), and easy to implement on various platforms (ie, an arduino)."
I'm in the process of building a Eurorack Faderfox which uses this protocol.
The Faderfox uses a Monome stype i2c connector TRS jack (tip is SDA, ring is SCL).
I understand that the ER-301 from Orthagonal Devices, the Monome Ansible & TXo also use i2c.
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The I2C bus is a standard bidirectional interface that uses a controller, known as the master, to communicate with slave devices. A slave may not transmit data unless it has been addressed by the master. Each device on the I2C bus has a specific device address to differentiate between other devices that are on the sameI2C bus. Many slave devices will require configuration upon start up to set the behavior of the device.
Links
MidiBox Hardware
Monome Aleph
ER 301
Circuit basics
I'll add to this page over time.
I'm not a Buchla technician so please let me know if there are any mistakes or BS.
It's also called rather confusingly IIC or i2c or the I²C (Inter-Integrated Circuit) interface.
Anyway, it's a digital communication protocol and it looks like it's becoming more common in the synthesizer world.
Buchla used this back in 2005 when Don developed the 200e.
He used this on the 200e's internal "power" bus (obviously it distributed more than just power):
Pin 8 = Yellow: i2c clock
Pin 9 = Green: i2c data
It appears that i2c uses just 2 "wires" to transmit the necessary data.
They are:
SDA (Serial Data) – The line for the master and slave to send and receive data.
SCL (Serial Clock) – The line that carries the clock signal.
Interestingly the Monome Aleph and the Teletype also use i2c.
According to their website:
" the bus is addressable (multiple devices on a chain), fast (400k), and easy to implement on various platforms (ie, an arduino)."
I'm in the process of building a Eurorack Faderfox which uses this protocol.
The Faderfox uses a Monome stype i2c connector TRS jack (tip is SDA, ring is SCL).
I understand that the ER-301 from Orthagonal Devices, the Monome Ansible & TXo also use i2c.
----------------------------------
The I2C bus is a standard bidirectional interface that uses a controller, known as the master, to communicate with slave devices. A slave may not transmit data unless it has been addressed by the master. Each device on the I2C bus has a specific device address to differentiate between other devices that are on the sameI2C bus. Many slave devices will require configuration upon start up to set the behavior of the device.
Links
MidiBox Hardware
Monome Aleph
ER 301
Circuit basics
I'll add to this page over time.
I'm not a Buchla technician so please let me know if there are any mistakes or BS.