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Communication Processor Module
E—End of Table
In tables with eight control characters, this bit is always zero.
0 = This entry is valid. The lower eight bits are checked against the incoming character.
1 = This entry is invalid and must be the last entry in the control characters table.
R—Reject Character
0 = The character is not rejected, but is written into the receive buffer. The buffer is
then closed and a new receive buffer is used if there is more data in the message.
A maskable interrupt is generated.
1 = If this character is recognized, it is not written to the receive buffer. Instead, it is
written to the RCCRP register and a maskable interrupt is generated. The current
buffer is not closed when a control character is received with the R bit set.
CHARACTER1–CHARACTER8—Control Character Values 1–8
These fields define control characters that will be compared to the incoming character. For
characters smaller than 8 bits, the most-significant bit must be zero.
RCCM—Received Control Character Mask
This value is used to mask the comparison of the CHARACTER1–CHARACTER8 fields.
The lower eight bits of the RCCM correspond to the lower eight bits of
CHARACTER1–CHARACTER8 and are decoded as follows:
0 = Mask this bit when the incoming character and CHARACTER1–CHARACTER8
fields are compared.
1 = The address comparison on this bit proceeds normally and no masking occurs.
Note: Bits 0 and 1 of the RCCM must be set or erratic operation will occur during the
control character recognition process.
RCCRP—Received Control Character Register
When a control character match is made and the R bit is set, the SCCx UART controller
writes the control character into the RCCRP and generates a maskable interrupt. The core
must process the interrupt and read the RCCRP before a second control character arrives.
If this does not occur, the SCCx UART controller overwrites the first control character.
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MPC823e REFERENCE MANUAL
MOTOROLA
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