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Intel Triple-Speed Ethernet Link detect LED lines malfunctioning?

Honored Contributor II



I've instantiated the Intel TSE IP Core in my design, testing on the Intel Arria 10 GX Development Kit board. From what I can tell it appears to be functioning: data can be sent and received, and the partner on the other side of the link shows auto-negotiation success and link up. 


However, I'm getting weird behavior from the IP core's LEDs. After an Ethernet cable is unplugged the led_an (auto-negotiation success) and led_link/led_panel_link (link up) remain illuminated. led_crs (activity detect) works as you'd expect. Neither of the error LEDs are illuminated and I see no other hint of a problem. 


If I unplug the cable, led_an and led_panel_link briefly turn off, but almost immediately re-illuminate even if the cable remains unplugged. led_link stays on no matter what. 


Any clues as to what might be happening here? What information can I provide to help? Attached is an image of the cable unplug event. I'm stumped. 


I'm setting the following registers, in this order, and confirmed they were set by reading them back. 


Address <- Value 

0x03 <- 0x04030201 // Mac upper 

0x04 <- 0x00000605 // MAC lower 

0x92 <- 0x00000D40 // Link timer lower 

0x93 <- 0x00000003 // Link timer upper 

0x80 <- 0x00009141 // PCS reset 

0x02 <- 0x0000023B // TSE Control (TX_ENA, RX_ENA, ETH_SPEED, PROMIS_ENA, PAD_ENA, TX_ADDR_INS)
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Were you ever able to figure this out? We're seeing the exact same behavior. Same register settings (which are basically the suggested registers from the User Guide).

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