MPC823 datasheet(49/74 Pages) MOTOROLA

49 / 74 page

Communication Processor Module

MOTOROLA

MPC823 REFERENCE MANUAL

16-427

• C/I_TXBD—The SMCx circuit interface channel transmit (TX) buffer descriptor is used

by the communication processor module to report information about the circuit interface

channel transmit byte.

R—Ready

0 =

The communication processor module clears this bit after transmission to

indicate that the buffer descriptor is now available to the core.

1 =

The core sets this bit to indicate that the data associated with this buffer

descriptor is ready for transmission.

Bits 1–7 and 14–15—Reserved

These bits are reserved and must be set to 0.

C/I DATA—Command/Indication Data Bits

This field represents a 4-bit data field for circuit interface channel 0 and a 6-bit data field

for circuit interface channel 1. It contains the data to be transmitted onto the circuit

interface channel. For circuit interface channel 0, bits 10-13 contain the 4-bit data field

and bits 8 and 9 are always written with zeros. For circuit interface channel 1, bits 8-13

contain the 6-bit data field.

• TEMP1–4—These bits are used internally by the RISC microcontroller.

16.11.8.3 SMCx GCI COMMANDS. The following commands are issued to the CPM

command register.

• INIT TX AND RX PARAMS—This command initializes the transmit and receive

parameters in the parameter RAM to their reset state and it is especially useful when

switching protocols on a given serial channel.

• TRANSMIT ABORT REQUEST—This receiver command can be issued when the

MPC823 implements the monitor channel protocol. When it is issued, the MPC823

sends an abort request on the A bit.

• TIMEOUT—This transmitter command can be issued when the MPC823 implements

the monitor channel protocol and it is usually issued because the device is not

responding or A bit errors are detected. The MPC823 sends an abort request on the E

bit at the time this command is issued.

OFFSET + 0

RESERVED

C/I DATA

RESERVED

MPC823 데이터시트(PDF) 49 Page - Motorola, Inc