DS33Z41 Quad IMUX Ethernet Mapper

FCS byte extraction discards the FCS bytes. If FCS extraction is enabled, the FCS bytes are extracted from the packet and discarded. If FCS extraction is disabled, the FCS bytes are stored in the receive FIFO with the packet. If FCS processing or packet processing is disabled, FCS byte extraction is not performed.

Bit reordering changes the bit order of each byte. If bit reordering is disabled, the incoming 8-bit data stream DT[1:8] with DT[1] being the MSB and DT[8] being the LSB is output to the Receive FIFO with the MSB in RFD[7] (or 15, 23, or 31) and the LSB in RFD[0] (or 8, 16, or 24) of the receive FIFO data RFD[7:0] (or 15:8, 23:16, or 31:24). If bit reordering is enabled, the incoming 8-bit data stream DT[1:8] is output to the Receive FIFO with the MSB in RFD[0] and the LSB in RFD[7] of the receive FIFO data RFD[7:0]. DT[1] is the first bit received from the incoming data stream.

Once all of the packet processing has been completed, The 8-bit parallel data stream is demultiplexed into a 32- bit parallel data stream. The Receive FIFO data is passed on to the Receive FIFO with packet start, packet end, packet abort, and modulus indications. At a packet end, the 32-bit word may contain 1, 2, 3, or 4 bytes of data depending on the number of bytes in the packet. The modulus indications indicate the number of bytes in the last data word of the packet.

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Maxim DS33Z41 specifications