Forum Discussion

JPrig's avatar
JPrig
Icon for New Contributor rankNew Contributor
3 days ago

Configurable transceiver enable

I need to enable transceiver channels in groups based on a board parameter read during board start-up. If the parameter is '0', channels 1 and 2 are enabled, channels 3 and 4 are disabled. If the parameter is '1', channels 3 and 4 are enabled and 1 and 2 are disabled. I want to explicitly disable the unused channels to save power and prevent them from driving outputs.

The only way to disable channels that I've figured out is to hold the input reset of the reset controller asserted. Then I'll need 2 reset controllers, one for each group of 2 channels. I'll also need 2 PLLs since they are interconnected with the reset controller.

Is this the way to do it or is there a better way?

Best regards,

Julia 

3 Replies

  • JonWay_altera's avatar
    JonWay_altera
    Icon for Frequent Contributor rankFrequent Contributor
    6 hours ago

    Hi Julia, 

     

    Could you send back the information for the following clarifying questions to make sure the problem is fully understood and to avoid proposing the wrong solution.

    • Which Altera device family and part number are you using, and which transceiver type (e.g., FGT, FHT, GTS)?
    • Is the board parameter static for the entire power‑up, or can it change dynamically after FPGA configuration?
    • Do channels 1–2 and 3–4 operate at the same line rate and reference clock, or do they have different requirements?
    • Are these channels used for a specific protocol (e.g., PCIe, Ethernet, JESD204, Aurora), or are they raw PHYs?
    • JPrig's avatar
      JPrig
      Icon for New Contributor rankNew Contributor
      3 hours ago

      Hi JonWay,

      the device is Cyclone 10 GX 10CX105YU484I6G and the transceiver is the 12.5Gbps transceiver. Though I will use it at a lower data rate.

      The board parameter is static during the entire power-up. The channels operate at the same line rate and have the same reference clock. The channels will be used with a custom protocol, so raw PHYs are instantiated.

      Best regards,

      Julia