mpc823rg Freescale Semiconductor, Inc, mpc823rg Datasheet - Page 794

• Manufacturer Part Number: mpc823rg
• Description: Mpc823 Powerquicc Integrated Communications Processor For Portable Systems
• Manufacturer: Freescale Semiconductor, Inc

Freescale Semiconductor, Inc.
Communication Processor Module
LC—Late Collision
This bit indicates that a collision occurred after the number of bytes defined for the LCW bit
in the PSMR–SCC Ethernet are transmitted. The SCCx Ethernet controller stops
transmitting and writes this bit after it finishes transmitting the associated data buffer.
RL—Retransmission Limit
This bit indicates when the transmitter fails a Retry Limit + 1 attempt to successfully transmit
a message because of repeated collisions on the medium. The SCCx Ethernet controller
writes this bit after it finishes transmitting the associated data buffer.
RC—Retry Count
This field indicates the number of retries required before this frame is successfully
transmitted. If RC = 0, then the frame is transmitted correctly the first time. If RC = 15 and
RET_Lim = 15 in the parameter RAM, then 15 retries are required. If RC = 15 and
RET_Lim > 15 in the parameter RAM, then 15 or more retries are required. The SCCx
Ethernet controller writes these bits after it finishes transmitting the associated data buffer.
UN—Underrun
This bit indicates that the SCCx Ethernet controller has encountered a transmitter underrun
condition while transmitting the associated data buffer. The SCCx Ethernet controller writes
this bit after it finishes transmitting the associated data buffer.
CSL—Carrier Sense Lost
This bit indicates that the carrier sense was lost during frame transmission. The SCCx
Ethernet controller writes this bit after it finishes transmitting the associated data buffer.
DATA LENGTH
This field represents the number of octets the SCCx Ethernet controller must transmit from
this buffer descriptor data buffer. It is never modified by the communication processor
module. The value of this field must be greater than zero. The SCCx Ethernet controller
writes these bits after it finishes transmitting the associated data buffer.
TX DATA BUFFER POINTER
This field contains the address of the associated data buffer, can be even or odd, and reside
in internal or external memory. This value is never modified by the communication processor
module. The SCCx Ethernet controller writes these bits after it finishes transmitting the
associated data buffer.
MPC823 REFERENCE MANUAL
MOTOROLA
For More Information On This Product,
Go to: www.freescale.com