Article ID: 000080260 Content Type: Troubleshooting Last Reviewed: 11/28/2013

Incorrect Register Value After Tx/Rx Reset

Environment

  • Quartus® II Subscription Edition
  • Ethernet
  • BUILT IN - ARTICLE INTRO SECOND COMPONENT

    Critical Issue

    Description

    Some of the Low Latency 10GbE MAC registers will have incorrect value after being reset with tx_rst_n or rx_rst_n.. This issue affects the following registers:

    • 0x0FE-0x0FF: Tx Underflow Truncated Data Frame Count
    • 0x0FC-0x0FD: Rx Overflow Truncated Packet Count
    • 0x0FE-0x0FF: Rx Overflow Dropped Packet Count
    • 0x140-0x17E: Tx Statistics (only affects register-based statistics)
    • 0x1C0-0x1FE: Rx Statistics (only affects register-based statistics)
    • 0x240: ECC Error Status
    Resolution

    To overcome this issue, write or read the following addresses to clear the registers as shown in table below.

    Registers

    Workaround

    0x0FE-0x0FF: Tx Underflow Truncated Data Frame Count

    After tx_rst_n, read at address 0x03E to clear the register.

    0x0FC-0x0FD: Rx Overflow Truncated Packet Count

    After rx_rst_n, read at address 0x0FC to clear the register.

    0x0FE-0x0FF: Rx Overflow Dropped Packet Count

    After rx_rst_n, read at address 0x0FE to clear the register.

    0x140-0x17E: Tx Statistics

    After tx_rst_n, write 0x1 to address 0x140 to clear the statistics counter.

    0x1C0-0x1FE: Rx Statistics

    After rx_rst_n, write 0x1 to address 0x1C0 to clear the statistics counter.

    0x240: ECC Error Status

    After tx_rst_n or rx_rst_n, read at address 0x240 to clear the registers.

    This issue will be fixed in a future version of the Low Latency 10GbE MAC MegaCore function.

    Related Products

    This article applies to 1 products

    Intel® Programmable Devices