• State
  • Replies 6 replies
  • Subscribers 33 subscribers
  • Views 75 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

DP83849IF: USB2 to 100BASE-FX

Nicolas Bouquet
Intellectual 470 points
Part Number: DP83849IF
Other Parts Discussed in Thread: TIDA-00306, , DP83869

Tool/software:

Hello,

I'm looking for a USB2 to 100 Mbps fiber interface. The USB host should see the interface as a new ETH interface. I plan to use any standard 1x9 SC Fiber Transceiver Module.

Is there a single chip solution to do that ?

Alternatively, I think I can use any USB to ETH converter and then a DP83849IF in copper to fiber mode (TIDA-00306 help a lot).

Any advice / idea or other device reference will help :)

Thanks

  • 0
    TI__Mastermind 36470 points

    Hello,

    Can you share what the end-goal is? Is it USB data converted to 100BASE-FX? If so, I would recommend using our DP83869 as this is our latest device which supports media conversion in both 100 and 1000 Mbps. 

    Can you also share what format the ETH coming from USB will be in? Is this going to be in MII or MDI format?

    Sincerely,

    Gerome

  • 0 in reply to Gerome Cacho
    Intellectual 470 points

    Hello,

    I have a electronic module based on a raspberry pi compute module v3, it expose only an USB2 port.

    I sometime need a direct ETH port : in this case, any USB to ETH device works.

    But sometime the link must be 300m, opto-isolated and without any EMI radiation. Only a fiber link is allowed.

    The ETH format is not already defined, it depends on which bridge I will use. MDI format is more probable.

    Nicolas

  • 0 in reply to Nicolas Bouquet
    TI__Expert 5610 points

    Hi Nicolas, 

    Thank you for your query. Gerome is OoO today, and will be looking to respond to your query by EoD Thursday.

    Sincerely,

    Vivaan

  • 0 in reply to Gerome Cacho
    Intellectual 470 points

    Thinking about it since 2 days, I think the DP83869 could be a nice solution. I plan to use a SFP socket and plug either a 100FX optical transceiver, either a 100Base-T RJ45 adapter.

    In both cases, the SFP module provides a LOS signal and the DP83869 has a SD input. Polarity is inverted, does just putting an inverter between LOS and SD will do the trick ?

    Assuming I will drive the DP83869 in RMII, when using the optical module, what is the good configuration of CFG_OPMODE @ 0x1DF ? 

    SFP modules are using SGMII signalling, so I suppose I should configure CFG_OPMODE = 3h = RGMII to SGMII, for any kind of SFP module (optical or RJ45). In this case, does the chip take care about the SD input ?

    Thank you
    Nicolas

     

  • 0 in reply to Nicolas Bouquet
    TI__Expert 5610 points

    Hi Nicolas, 

    Thank you for your query. Gerome is OoO today, and will be looking to respond to your query by EoD Thursday.

    Sincerely,

    Vivaan

  • 0 in reply to Vivaan Jaiswal
    TI__Mastermind 36470 points

    Hello,

    DP83869 will not support RMII; only MII, RGMII, or SGMII.

    Regarding SD polarity, a buffer can suffice or you may invert the polarity of SD. I would recommend trying out this configuration on our DP83869 EVM if you are looking to use FX to CU media conversion. 

    Sincerely,

    Gerome