In the sample code "MSP430F55xx_uscib0_i2c_10.c", it provides a demo about I2C read multi-bytes from target, however,it just loop 5 times in USCUB0.
My problem is that, how can the controller know the last byte and send NACK? It seems different from the I2C in MSPM0?
In MSPM0, I need to first define the number of bytes need to read, then how about MSP430?
Hi Kun,
Within the USCI_B0 ISR there is a set of the UCTXSTP bit inside the UCB0CTL1register.
This tells the controller to generate a stop after the next received byte, which in controller receive mode translates to a NAK, followed by a stop, per the family User's Guide:
You do still define the number of bytes you want to read, in the MSP430 code however, this is done with RXByteCtr, and the number of bytes read back is manually incremented.
Best Regards,
Brandon Fisher
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