SH7670 Datasheet, PDF (516/1292 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7670 Series

Section 13 Ethernet Controller Direct Memory Access Controller (E-DMAC)
No. 31
16 15
0
0
1
2
3 IPv4/IPv6/others (Decision)
4
Payload length
5 Next header*¹
Transmit IP
6
Transmit IP
7
Transmit IP
8
Transmit IP
9
Transmit IP
Receive IP
10
Transmit IP
11
Transmit IP
12
Transmit IP
13
Receive IP
Next header*¹ Header length*²
The content of an extension header is not the target
of checksum calculation.
Data
Note: 1. Calculation applies only to TCP/UDP. Calculation requires an
expansion to {8'h00, next header[7:0]}.
2. This is changed to the octet basis and undergoes a subtraction
during checksum calculation.
(2) All-Data Checksum Calculation Function of Skipped Bytes Designation Type
The data equivalent to the number of bytes specified by SB5 to SB0 is skipped from the beginning
of a packet, and checksums are calculated on all of the subsequent valid data. (Example: 14-byte
skip)
No. 31
16 15
0
0
1
SB[5:0]OE
2
3
4
5
6
7
Data to be calculated
8
9
10
11
Rev. 1.00 Nov. 14, 2007 Page 490 of 1262
REJ09B0437-0100