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MSP430F6749: I2C clock of UCB0SCL stop when read data from EEPROM

Part Number: MSP430F6749

dear all

Iam Emad Hamdy hardware engineer in El sewedy Electrometer Egypt branch , and we have used MSP430F67491A MCU in a  single phase meter design, and we faced problem in the communication with EEPROM  using  UCB0  port , the problem in the last byte of frame and after ACK the clock doesn't stop and generate extra 5 clocks  and the SDA latched low, i attched pic for this case and and file 

  • Hi Emad,

    Thanks for your post. Unfortunately, I'm unable to access your attachment since it's in .rar format. Could you reattach any scopeshots showing this behavior?

    Can you give more background information about how this issue started? Is this an existing design and something was changed in the code or the BOM that may have caused this or is this a new design and hence a new issue?

    In the meantime, please read through the MSP430F6749's erratasheet. Unfortunately, there are several eUSCI-related errata. Specifically, USCI36 mentions UCLKI is not usable in I2C master mode for EUSCIB. Also, please read through the I2C section in the Solutions to Common eUSCI and USCI Serial Communication Issues on MSP430 MCUs app note.