Motorola MPC823e - Page 840

Communication Processor Module
16-386 MPC823e REFERENCE MANUAL MOTOROLA
SMC
COMMUNICATION
16
PROCESSOR MODULE
• The parameter RAM values that pertain to the SMCx transmitter can only be written
when the TEN bit in the SMCMR is zero or after the STOP TRANSMIT command is
issued, but before the RESTART TRANSMIT command is issued.
• The parameter RAM values that pertain to the SMCx receiver can only be written when:
❏ The REN bit in the SMCMR is zero.
❏ The receiver is previously enabled after the ENTER HUNT MODE command is
issued.
❏ The CLOSE RX BD command is issued before the REN bit is set.
Table 16-36. SMCx (UART and Transparent) Parameter RAM Memory Map
ADDRESS NAME WIDTH DESCRIPTION
SMCx Base + 00 RBASE Half-Word RX Buffer Descriptor Base Address
SMCx Base + 02 TBASE Half-Word TX Buffer Descriptor Base Address
SMCx Base + 04 RFCR Byte RX Function Code
SMCx Base + 05 TFCR Byte TX Function Code
SMCx Base + 06 MRBLR Half-Word Maximum Receive Buffer Length
SMCx Base + 08 RSTATE Word RX Internal State
SMCx Base + 0C RPTR Word RX Internal Data Pointer
SMCx Base + 10 RBPTR Half-Word RX Buffer Descriptor Pointer
SMCx Base + 12 RCNT Half-Word RX Internal Byte Count
SMCx Base + 14 RTMP Word RX Temp
SMCx Base + 18 TSTATE Word TX Internal State
SMCx Base + 1C TPTR Word TX Internal Data Pointer
SMCx Base + 20 TBPTR Half-Word TX Buffer Descriptor Pointer
SMCx Base + 22 TCNT Half-Word TX Internal Byte Count
SMCx Base + 24 TTMP Word TX Temp
SMCx Base + 28 First Word of Protocol-Specific Area
SMCx Base + 36 Last Word of Protocol-Specific Area
NOTE: You are only responsible for initializing the items in bold.
SMCx Base = (IMMR & 0xFFFF0000) + 0x3E80 (SMC1) and 0x3F80 (SMC2).