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Line 6: − * Does the CP2200/1 filter packets based on MAC or do all packets get passed to the FPGA? Line 18:
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* How will the FPGA obtain the MAC address of the PC?
* How will the FPGA obtain the MAC address of the PC?
== Structure of a packet ==
== Structure of a packet ==
=== Receiving ===
=== Receiving ===
The CP2200/1 appears to give access to the entire 64-byte (minimum) packet, which would include everything on the above diagram except for the "Preamble and Start Frame Delimiter". It seems that the CP2200/1 can be programmed to accept only packets addressed to itself; in that case the FPGA can strip away and ignore the first 14 bytes (it does not need the length field, as we define our own standard for the packets below, using the first data byte to specify the type of packet). From there the FPGA can parse the data field according to the below specifications. If the CP2200/1 supplies all packets, then the FPGA will need to filter packets by way of the destination MAC address.
The CP2200/1 appears to give access to the entire 64-byte (minimum) packet, which would include everything on the above diagram except for the "Preamble and Start Frame Delimiter". The CP2200/2 can be programmed to filter out any packets not addressed to it. However, it only verifies the first 5 bytes of the MAC address. Checking the 6th byte and using the skip procedure is left to the FPGA. For good packets the FPGA can strip away and ignore the first 14 bytes (it does not need the length field, as we define our own standard for the packets below, using the first data byte to specify the type of packet). From there the FPGA can parse the data field according to the below specifications.
== Our packets ==
== Our packets ==