MPC823 datasheet(20/74 Pages) MOTOROLA

20 / 74 page

Communication Processor Module

16-398

MPC823 REFERENCE MANUAL

MOTOROLA

FR—Framing Error

This bit indicates that a character with a framing error has been received and is located in

the last byte of this buffer. A framing error is a character without a stop bit. A new receive

buffer is used to receive additional data. The communication processor module writes this

bit after the received data is in the associated data buffer.

PR—Parity Error

This bit indicates that a character with a parity error has been received and is located in the

last byte of this buffer. A new receive buffer is used to receive additional data. The

communication processor module writes this bit after the received data is in the associated

data buffer.

OV—Overrun

This bit indicates that a receiver overrun has occurred during message reception. The

communication processor module writes this bit after the received data is in the associated

data buffer.

DATA LENGTH

This field represents the number of octets the communication processor module writes into

this buffer descriptor data buffer. After the data is received in the associated data buffer, the

communication processor module writes this field once the buffer descriptor closes.

RX DATA BUFFER POINTER

This field always points to the first location of the associated data buffer and must be even.

The buffer can reside in internal or external memory. The communication processor module

writes this bit after the received data is in the associated data buffer.

Note: The actual amount of memory allocated for this buffer must be greater than or

equal to the MRBLR entry.

MPC823 Datasheet(PDF) 20 Page - Motorola, Inc