Motorola MPC823e Reference Manual page 827

16.10.8.6 USB ENDPOINT CONFIGURATION REGISTERS 0–3. There are four 16-bit,
memory-mapped, read/write USB endpoint configuration (USEPx) registers.
USEP0–USEP3
BIT 0 1 2
FIELD EPN
RESET 0
R/W R/W
ADDR (IMMR & 0xFFFF0000) + 0xA04 (USEP0), 0xA06 (USEP1), 0xA08 (USEP2), 0xA0A (USEP3)
EPN— Endpoint Number
This field defines the supported endpoint number. It is used in slave mode and ignored in
host mode.
Bits 4–5 and 8–9—Reserved
These bits are reserved and must be set to 0.
TM—Transfer Mode
00 = Control.
01 = Interrupt.
10 = Bulk.
11 = Isochronous.
MF—Enable Multi-Frame
This bit allows loading of the next transmit packet into the FIFO before the previous packet
finishes transmitting. This bit must be set to zero, unless the endpoint is configured for
isochronous transfer mode or the endpoint is configured as a host (endpoint 0 only).
0 = The transmit FIFO can hold only one packet.
1 = The transmit FIFO can hold more than one packet.
RTE—Retransmit Enable
This bit must be set to zero for an endpoint configured for isochronous transfer mode.
0 = No retransmission.
1 = Automatic frame retransmission is enabled. The frame is retransmitted if a transmit
an error occurred (time-out).
Note: The RTE bit can only be set if the transmit packet is contained in a single buffer.
Otherwise, retransmission must be handled by software intervention.
MOTOROLA
3 4 5 6 7
RESERVED TM RESERVED
0 0
R/W R/W
MPC823e REFERENCE MANUAL
Communication Processor Module
8 9 10 11 12
MF RTE THS
0 0 0 0
R/W R/W R/W R/W
13 14 15
RHS
R/W
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