23.17 SCC UART Receive Buffer Descriptor (RxBD)
The CPM uses RxBDs to report on each buffer received. The CPM closes the current buffer,
generates a maskable interrupt, and starts receiving data into the next buffer after one of the
following occurs:
¥ A user-deÞned control character is received.
¥ An error occurs during message processing.
¥ A full receive buffer is detected.
¥ A MAX_IDL number of consecutive idle characters is received.
¥ An
ENTER HUNT MODE
¥ An address character is received in multidrop mode. The address character is written
to the next buffer for a software comparison.
Figure 23-7 shows an example of how RxBDs are used in receiving.
MOTOROLA
Part V. The Communications Processor Module
or
command is issued.
CLOSE RXBD
Chapter 23. SCC UART Mode
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