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M0A21/M0A23 Series
May 06, 2022
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ANUAL
6.12.4.8 Wake-up
The protocol-related wake-up functional information is located in the Wake-up Control Register
(USCI_WKCTL) and in the Wake-up Status Register (USCI_WKSTS). These registers are shared
between the available protocols. As a consequence, the meaning of the bit positions in these registers
is different within the protocols.
6.12.4.9 PDMA
The USCI supports PDMA transfer function. When PDMAEN (USCI_PDMACTL [3]) is set to 1, the
PDMA function is enabled.
When TXPDMAEN (USCI_PDMACTL [1]) is set to 1, the controller will issue request to PDMA controller
to start the PDMA transmission process automatically.
When RXPDMAEN (USCI_PDMACTL [2]) is set to 1, the controller will start the PDMA reception
process. USCI will issue request to PDMA controller automatically when there is data in the receive
FIFO buffer.
In UART function, the requirement of RXPDMAEN will be cleared and hold if there is any error condition
events including frame error, parity error or break detection. The user shall read out the current data
and then the requirement of RXPDMAEN will send to the PDMA module in the next data.