21.4.7 Serial Data Reception

When the TPI physical layer is in receive mode, data reception is started as soon as a start bit has been detected. Each bit that follows the start bit will be sampled at the rising edge of the TPICLK and shifted into the shift register until the second stop bit has been received. When the complete frame is present in the shift register the received data will be available for the TPI access layer.

There are three possible exceptions in the receive mode: frame error, parity error and break detection. All these exceptions are signalized to the TPI access layer, which then enters the error state and puts the TPI physical layer into receive mode, waiting for a BREAK character.