r5s77631ay266bgv Renesas Electronics Corporation., r5s77631ay266bgv Datasheet - Page 1059

• Manufacturer Part Number: r5s77631ay266bgv
• Description: Renesas 32-bit Risc Microcomputer Superhtm Risc Engine Family Sh-4a Series
• Manufacturer: Renesas Electronics Corporation.

23.6
23.6.1
This LSI is capable of calculating the checksum data of the received frames. Only the data fields
of the Ethernet frames are subject to calculation. Specifically, a data field follows the length/type
field and is followed by the CRC field. Calculation involves 16-bit addition only; it does not
involve bit reversal.
Note: Also for the frames with VLANTag inserted, the 15th byte from the top and the following
23.6.2
The TSU of this LSI supports up to 100BASE-T data transfers. Therefore, even when The TSU of
this LSI is used with 1000BASE-T, the transfer performance is equal to that with 100BASE-T.
bytes before the CRC field are subject to calculation.
Usage Notes
Checksum Calculation of Ethernet Frames
Notes on TSU Use
Schematic of an Ethernet frame
(without VLANtag)
Data (46 to 1500 bytes)
Destination address
Source address
CRC (4 bytes)
Type (2 bytes)
(6 bytes)
(6 bytes)
Figure 23.38 Data Subject to Checksum Calculation
Data subject to
checksum
calculation
Schematic of an Ethernet frame
(with VLANtag)
Section 23 Gigabit Ethernet Controller (GETHER)
Destination address
Source address
Data (60 bytes)
CRC (4 bytes)
Type (2 bytes)
VLANtag
(6 bytes)
(6 bytes)
(4 bytes)
Rev. 1.00 Oct. 01, 2007 Page 993 of 1956
Data subject to
checksum
calculation
REJ09B0256-0100