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(b)
Receive Descriptor 1 (RD1)
RD1 specifies the receive buffer length (maximum 64 kbytes).
Bit
Bit Name
31 to 16
RBL
15 to 0
RDL
(c)
Receive Descriptor 2 (RD2)
RD2 specifies the 32-bit receive buffer start address. The receive buffer start address must be on a
longword boundary.
Section 21 Ethernet Controller Direct Memory Access Controller (E-DMAC)
Initial
value
R/W
Description
All 0
R/W
Receive Buffer Length
These bits specify the maximum reception byte length
in the corresponding receive buffer.
The transfer byte length must align with a 16-byte
boundary (bits 19 to 16 cleared to 0). The maximum
receive frame length with one frame per buffer is
1,514 bytes, excluding the CRC data. Therefore, for
the receive buffer length specification, a value of
1,520 bytes (H'05F0) that takes account of a 16-byte
boundary is set as the maximum receive frame
length.
All 0
R/W
Receive Data Length
These bits specify the data length of a receive frame
stored in the receive buffer.
The receive data transferred to the receive buffer
does not include the 4-byte CRC data at the end of
the frame. The receive frame length is reported as the
number of words (valid data bytes) not including this
CRC data.
Rev. 1.00 Mar. 12, 2008 Page 825 of 1178
REJ09B0403-0100
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