Serial Management Controllers (SMCs )
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 27-15
Data length represents the number of octets the CP writes into the buffer. After data is received in buffer,
the CP only writes them once as the BD closes. Note that the memory allocated for this buffer should be
no smaller than MRBLR. The Rx data buffer pointer points to the first location of the buffer and must be
even. The buffer can be in internal or external memory. Figure27-7 shows the UART RxBD process,
showing RxBDs after they receive 10 characters, an idle period, a nd five characters (one with a framing
error). The example assumes that MRBLR = 8.
12 PR Parity error. Set when a character with a parity error is received in the last byte of the buffer. A new
buffer is used for additional data. The CP writes PR after received data is in the buffer.
13 Reserved, should be cleared.
14 OV Overrun. Set when a receiver overrun occurs during reception. The CP writes OV after the received
data is in the buffer.
15 Reserved, should be cleared.
Table27-7. SMC UART RxBD Field Descriptions (continued)
Bit Name Description