| Electronics Forum |
Help
Search
Members
Calendar
|
| Welcome Guest ( Log In | Register ) | Resend Validation Email |
![]() ![]() ![]() |
| Mattyz |
Posted: April 11, 2012 07:08 pm
|
![]() Newbie ![]() ![]() Group: Members+ Posts: 16 Member No.: 35,624 Joined: August 25, 2011 |
Hello everybody, I'm reading something about the Ethernet protocol that is going to help me for my next project and I'd like to know if what I read is correct.
The ethernet frame structure is composed by: - Preamble: 7 bytes, all of them assume the value 0xAA (b'10101010') - SFD (Start Frame Delimiter): 1 byte, 0xAB (b'10101011') - MAC destination: 6 bytes, physical address of the receving device (* need to know more about this, can I send any number between 0x000000 and 0xFFFFFF?) - MAC source: 6 bytes, physical address of the sending device (* need to know more about this, can I send any number between 0x000000 and 0xFFFFFF?) - Length: 2 bytes, specifies the length of the "Data packet" (this number must be between 46 and 1500) - Data: 46<=bytes<=1500, data I want to send (what if I want to send less then 46 bytes?) - FCS (Frame Check Sequence): 4bytes, * I have no idea about how it works - Pause: 12 bytes (I guess they're all 0x00 right?) Preamble, SFD and Pause bytes are not necessary. Is it correct? Is there something else I should know (in addition to what I said I don't now)? Thanks for your help |
![]() |
![]() ![]() ![]() |
:: support us ::