Motorola MPC823e Reference Manual page 814

Communication Processor Module
The V bit is set if the SOF token was received error-free.
Table 16-35. Endpoint Parameters Block
ADDRESS
Base + 00
Base + 02
Base + 04
Base + 05
Base + 06
Base + 08
Base + 0a
Base + 0c
Base + 10
Base + 14
Base + 16
Base + 18
NOTE: You are only responsible for initializing the items in bold. Also, Base = (EP x PTR).
• RBASE and TBASE—The receive and transmit buffer descriptor base address entries
define the starting point in the dual-port RAM for the set of buffer descriptors to receive
and transmit data. This provides a great deal of flexibility in partitioning the buffer
descriptors for the USB controller. By setting the W bit in the last buffer descriptor in
each list, you can select how many buffer descriptors to allocate for the transmit and
receive side of the USB controller. However, you must initialize these entries before
enabling the USB controller. Furthermore, you must not configure buffer descriptor
tables of the USB to overlap any other serial channel's buffer descriptors or erratic
operation will occur.
Note: RBASE and TBASE must contain a value that is divisible by eight.
16-360
NAME WIDTH
RBASE Half Word
TBASE Half Word
RFCR Byte
TFCR Byte
MRBLR Half Word
RBPTR Half Word
TBPTR Half Word
TSTATE Word
TPTR Word
TCRC Half Word
TBCNT Half Word
RES 8 Bytes
MPC823e REFERENCE MANUAL
DESCRIPTION
RX Buffer Descriptor Base Address
Tx Buffer Descriptor Base Address
RX Function Code
TX Function Code
Maximum Receive Buffer Length
RX Buffer Descriptor Pointer
TX Buffer Descriptor Pointer
TX Internal State
TX Internal Data Pointer
TX Temp CRC
TX Internal Byte Count
Reserved
MOTOROLA