vhdl code for crc32 checksum

[anupam]

Hi,
can any body tell me that how the crc32 is calculated for ethernet frames
and which byte is transmitted first . I am designing ethernet to pcm
converter (for 32 time slots)in FPGA.
Thanx in Advance.
Anupam

 

[Mike Treseler]

anupam wrote:

Hi,
can any body tell me that how the crc32 is calculated for ethernet frames
and which byte is transmitted first . I am designing ethernet to pcm
converter (for 32 time slots)in FPGA.

LSB of the first byte is first on the line.
http://groups.google.com/groups?q=vhdl+crc+ethernet+bit+order

-- Mike Treseler

 

[anupam]

Hi Mike
First byte means , first byte from left or first byte from right.
Regards
anupam

 

[Allan Herriman]

On Mon, 06 Sep 2004 03:38:40 -0400, "anupam" <anupam@coraltele.com>
wrote:

Hi Mike
First byte means , first byte from left or first byte from right.

Bit and Byte order for Ethernet is well defined in the IEEE 802.3
standard.

It can be downloaded for free:
http://standards.ieee.org/getieee802/portfolio.html

Regards,
Allan

 

[Kai Harrekilde-Petersen]

Allan Herriman <allan.herriman.hates.spam@ctam.com.au.invalid> writes:

On Mon, 06 Sep 2004 03:38:40 -0400, "anupam" <anupam@coraltele.com
wrote:

Hi Mike
First byte means , first byte from left or first byte from right.

Bit and Byte order for Ethernet is well defined in the IEEE 802.3
standard.

To be more direct:

+------------+------------+----+------//------+--------+
| DMAC | SMAC | T/L| DATA | FCS |
+------------+------------+----+------//------+--------+

Increasing time ---->

The first byte of the Destination MAC Address (DMAC) is the most
significant byte (bits 47 downto 40), and least significant bit (ie
bit 40) first. I presume this is why bit 40 is the multicast bit in
the address.

Note that the FCS is actually transmitted in a different order.
As Allan wrote, look the in the IEEE standard.

Regards,


Kai
--
Kai Harrekilde-Petersen <khp(at)harrekilde(dot)dk>