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TJohn's avatar
TJohn
Icon for New Contributor rankNew Contributor
6 years ago

Triple-Speed Ethernet MegaCore Function user guide, ug_ethernet.pdf, figure 8.1 shows ff_tx_clk and ff_rx_clk at 110 MHz, but table 8.1 lists a recommended frequency of 100 MHz, which is right?

This disagreement is present in user guides versions, 14.0, 15.0, 15.1 as figures 9.1 and table 9.1. In versions 16.0, 16.1 and 17.1 it is listed as figures 8.1 and table 8.1 as in the question.

2 Replies

  • Vicky1's avatar
    Vicky1
    Icon for Regular Contributor rankRegular Contributor

    Hi,

    Thanks for your patience & cooperation.

    I checked it internally & it`s typo in Figure & it`s description & the correct frequency is 100 MHz as mentioned in table.

    Thanks to pointing out it to us, it will update while document upgradation.

    Thanks,

    Vicky

  • Vicky1's avatar
    Vicky1
    Icon for Regular Contributor rankRegular Contributor

    Hi,

    In addition, the input clock frequency for ff_tx_clk and ff_rx_clk signals to meet 1G bandwidth & it depends on width of FIFO that used while configuration. If width of the FIFO is 32-bit then these signal should have input clock at least 100 MHz & if it is 8-bit , then it needs to be at least 125 MHz.

    Regards,

    Vicky