SPRUHM9H October 2014 – May 2024 TMS320F28075 , TMS320F28075-Q1 , TMS320F28076
When the I2C module is a receiver (master or slave), the I2C module can acknowledge or ignore bits sent by the transmitter. To ignore any new bits, the I2C module must send a no-acknowledge (NACK) bit during the acknowledge cycle on the bus. Table 19-5 summarizes the various ways you can allow the I2C module to send a NACK bit.
I2C Module Condition | NACK Bit Generation Options |
---|---|
Slave-receiver modes |
Allow an overrun condition (RSFULL = 1 in I2CSTR) Reset the module (IRS = 0 in I2CMDR) Set the NACKMOD bit of I2CMDR before the rising edge of the last data bit you intend to receive |
Master-receiver mode AND Repeat mode (RM = 1 in I2CMDR) |
Generate a STOP condition (STP = 1 in I2CMDR) Reset the module (IRS = 0 in I2CMDR) Set the NACKMOD bit of I2CMDR before the rising edge of the last data bit you intend to receive |
Master-receiver mode AND Nonrepeat mode (RM = 0 in I2CMDR) |
If STP = 1 in I2CMDR, allow the internal data counter to count down to 0 and thus force a STOP condition If STP = 0, make STP = 1 to generate a STOP condition Reset the module (IRS = 0 in I2CMDR) Set STP = 1 to generate a STOP condition Set the NACKMOD bit of I2CMDR before the rising edge of the last data bit you intend to receive |