MSP430FR2522: slave i2c sw simultion on GPIO

Terry Deng

Part Number: MSP430FR2522

customer need slave i2c on fr2522 to communicate with host mcu，but the hardware i2c pin is occupied by captive function，do we have reference code to simulte sw slave i2c on general gpio？

over 4 years ago

0 Yiding Luo over 4 years ago

TI__Expert 5490 points

Hello Terry,

They can remap the I2C function to other pins on the MSP430FR2522 20 pin RHL package.
The primary eUSCI_B0 I2C pins are Pin 19 and Pin 20 which are also shared with CAP IOs. The secondary eUSCI_B0 I2C pins are Pin 9 and Pin 10 which are not shared with CAP IOs.

Thanks,
Yiding

0 Terry Deng over 4 years ago in reply to Yiding Luo

TI__Intellectual 2485 points

hi yiding，thanks your advice. customer cannot accept 20pin QFN package，so we have to consider sw i2c on 16pin package

0 Yiding Luo over 4 years ago in reply to Terry Deng

TI__Expert 5490 points

Hello Terry,

Here is the app note on MSP430 SW I2C.
www.ti.com/lit/slaa703
This software solution supports transactions on I2C bus with an SCL clock frequency of up to 100 kHz for master and slave.
I would still recommend to use 20pin QFN package if possible.

Thanks,
Yiding

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MSP430FR2522: slave i2c sw simultion on GPIO