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DP83869EVM: LED behavior

Prodigy 160 points

Replies: 9

Views: 222

Part Number: DP83869EVM

Hello,

I use the DP83869EVM eval board to evaluate the media converter chip in the goal to make a 100/1000Mbps converter. I know how switching between 100M to 1G but I don’t understand how the 3 LED works. I really need information about it.

You can find my configuration in 1Gbps media converter here:

 

1)      Why the LED in yellow still power-on when the traffic is above 10Mbps? Is there a solution to have a blinking?

2)      About LED in red, the one on the left is marked (silkscreen) as LINK and the one on the right is marked as 1000BT LINK.

 In datasheet, page 47/126, it said:

•     In 1000-Mbps media convertor mode, the link LED corresponds to 1000M link on Copper interface. If link speed is changed then Link LED cannot be used.

•     In 100-Mbps media convertor mode, the link LED corresponds to 100M link on Copper interface. If link speed is changed then Link LED cannot be used.

So, I would to know if the silkscreen is false because 1000BT (1000 BASE-T = Copper link). I think the marking is inverted between these LED, right?

 

3)      Other question, is it possible to have an activity LED for the SFP and a second for the Copper activity? Those 2 LED needs traffic blinking of course.

Thanks ,

BR

Alex

  • Hi Alex,

    You can change the function of the LEDs using register 0x18 and 0x19. The detailed description is available in the datasheet. For your other questions, I will get back to you by Wednesday. 

    -Regards

    Aniruddha

  • In reply to Aniruddha Khadye:

    Hi Aniruddha,

    I forgot to said in this post, my converter wont have any controller so it won't possible to change register in the future.

    No solution without µC?

    Whats about my second question?

    Thanks,

    BR

    Alex

  • In reply to AlexB38:

    Hi Aniruddha,

    any news? Could you please help here?

    Thanks a lot in advance.

    Best regards,

    Massimiliano.

  • In reply to Massimiliano De Cristofaro:

    Hi,

    No solution? I really need this information to continue. My project is in standby due to this problem...

    Thank you

    BR

    Alex

  • In reply to AlexB38:

    Team,

    please answer asap. It is urgent.

    Thanks,

    Massimiliano

  • In reply to Massimiliano De Cristofaro:

    Hi Alex,

    The silk screen is created with respect to Copper Ethernet mode. "Link" is to indicate any kind of link: 10, 100, or 1000Mbps. "1000BT_Link" is used to indicate only 1000Base-T. Here is how the truth table would look like for copper ethernet

    'LINK' LED '1000BT_LINK' LED Result
    OFF OFF No Link
    ON OFF Either 10M or 100M link
    OFF ON Not Applicable
    ON ON 1000M link

    By default, Link indication functionality is dedicated on LED_0 pin. This can be changed by software settings. The comments on datasheet page 47 are for LINK LED which would mean LED_0 in this case. 

    Unfortunately, there is not way to change the default LED functionality without software configuration. If anything other that default features are needed on LED pin, a uC will have to make changes to the register settings.

    -Regards

    Aniruddha

  • In reply to Aniruddha Khadye:

    Hi,

    Thank you for the response. I will find another solution to control LEDs.

    I have another question about the pin supply. In the datasheet (page 5, 6 & 7), some pins have information about the voltage domaine like the LED_0 pin which is referenced to the VDDIO voltage. Whats about the others? In the MDIO pin description, it is written this pin must be pulled up with a 1.5kO resistor but to which voltage?

    Can you fonfirm that all the IO (LED, INT_N, RESET_N, MDIO/MDC, MII pins, JTAG pins) are referenced to the VDDIO supply?

    Thank you

    BR

    Alex

  • In reply to AlexB38:

    Hi Alex,

    Yes, the IO pins are in the VDDIO Domain.

    -Regards

    Aniruddha

  • In reply to Aniruddha Khadye:

    Hi Aniruddha,

    Thank you for reply!

    BR

    Alex

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