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Sharing Nunchucky with MCP23017 i2c
Moderators: adafruit_support_bill, adafruit

Sharing Nunchucky with MCP23017 i2c

by rahatmaini on Wed Feb 20, 2013 10:58 pm

I have asked about sharing i2c pins on this forum before, unfortunately the response was not as helpful as I would have liked. I would like to know how I can share the A4 and A5 pins (i2c bus) with multiple devices.

The concept just seems weird. Sharing 2 pins used together with multiple devices, controlling individually with software.

Thanks. :?:

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Re: Sharing Nunchucky with MCP23017 i2c

by adafruit_support_rick on Thu Feb 21, 2013 11:27 am

I2C is a non-arbitrated master-slave bus architecture. Each device on the bus must have a unique 7-bit address. On each transaction, the master (i.e., the arduino) sends out the address of the device it wants to talk to. Only that device will respond.

It's very Victorian. Devices will only speak when spoken to. :wink:

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Location: Buffalo, NY

Re: Sharing Nunchucky with MCP23017 i2c

by stroffduino on Thu Feb 21, 2013 7:58 pm

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