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Visitor
Visitor
7,524 Views
Registered: ‎09-05-2013

leds connected to 88E1111 Phy not glowing

Dear All,

 

i have designed a board based on SP605...

 

the leds connected to PHY 88E1111 are not blinking....

 

after performing pheripheral test, all have got passed...

 

all VCC (2.5, 1.2, PHY_AVDD) are correct

 

TX_clk coming correct...

 

after enabling debug option for lwip in bsp settings, i noted that phy is getting detected at address7... echo server is also started..

 

but none of the leds are glowing so no link....

 

ping geeting failed...

 

kindly guide me towards the solution for this problem....

 

thanks & regards,

aditya

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Professor
Professor
7,514 Views
Registered: ‎08-14-2007

The FPGA has very little to do with the PHY link side, so it's likely that your problem is something very basic like:

 

1) Missing 25 MHz clock input to the PHY chip

 

2) Incorrect strapping resistor configuration on the PHY

 

3) Incorrect connections between PHY, magnetics and RJ-45 jack.

 

If you have copied the circuit from the SP605 design, make sure you haven't made copying errors and that you check the SP605 user guide and errata (if any) to check that you have used the correct components and option connections.

-- Gabor
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Visitor
Visitor
7,492 Views
Registered: ‎09-05-2013

dear sir,

 

thanks a lot....

 

when i carefully noticed 3 pind in rj45 were connected wrongly, so i desoldered the RJ45 connector and i have put the jumpers and made the connections correct. BUT STILL the leds are not glowing...

 

please guide me..

 

thanks & regards,

aditya

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Visitor
Visitor
7,491 Views
Registered: ‎09-05-2013

also sir i forgot to mention that i have checked my schematics with sp605 and altys board...there is no apparent difference as of now..

altys board is having the same fpga as that on my board, i made one test project for altys board and it worked in first run...

fyi
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Visitor
Visitor
7,490 Views
Registered: ‎09-05-2013

dear sir,

 

plz take a look at my schematics for ethernet...

 

sir i have verified follwing things:

1. 25MHZ clk

2. strapping resistor configuration is perfect as per sp605 and altys board

3. connection between rj45 and phy is also perfect now...

 

plz guide

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Visitor
Visitor
7,489 Views
Registered: ‎09-05-2013

kindly find the attached schematics which i forgot to add in my previous reply

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Professor
Professor
7,479 Views
Registered: ‎08-14-2007

There's nothing obviously wrong with your schematic.  There could still be issues with layout, but I imagine they'd need to be pretty bad to prevent the PHY from coming up at all.  The only thing I see that is very different from my board is the magnetics Vcc pin tied to PHY_AVDD0, where my board uses +1.8V for the magnetics.

 

Check the PHY_RESET signal.  This is active low reset, so it should be high to allow the PHY to run.

 

Check the PHY_TXC_GTXCLK signal.  It should have 125 MHz if the PHY's PLL is running.  If not, you need to check that your 25 MHz is clean and that the power supplies are properly filtered.

 

Other things that I can't check are:

 

magnetics - make sure that your jack with integrated magnetics is similar to the one on the SP605 board, or at least uses the recommended magnetics topology for the PHY.  I used a Tyco 5-6605463-6 on my board.

 

routing - make sure that the MDIP/MDIN pairs are routed with 100 ohm differential impedance and properly length matched.  47 Ohm resistors (I used 49.9 Ohm in my board) should be at the connector end of the signal traces.

 

If you suspect that the signal integrity may be an issue, try running at 100 Mbps instead of 1 Gbps.  I usually grab an old 10/100 Mbps hub for this sort of testing.  If you have a 1 Gbps switch you could try that as well, instead of connecting directly to a P.C.

-- Gabor
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Visitor
Visitor
7,474 Views
Registered: ‎09-05-2013

dear sir,

 

thanks a lot for your pointers..

 

I have checked that the reset is high...

 

i am not working in gigabit mode...

 

i am using MII interface, where it has nothing to do with GTX_CLK...

 

i tried to work in 100MBps mode and 10Mbps mode.... then also no led blinking..

 

also sir i noticed 2.5 Mhz clk at TX_clk, and 125Mhz ar RX_clk (sir i highly suspect something wrong here)

 

sir i have also checked component wise connectivity but that also dint helped....

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Visitor
Visitor
7,473 Views
Registered: ‎09-05-2013

also sir, i am having SP605 and altys development board. i used the fpga pressent on altys board and rest all the components are from SP605 board. I copied the same BOM...

echo server i am able to run on both board...

one more point sir that i conneted by board to 10/100 switch, two different PCs and i have also changed my PC's ethernet adadpter settings to 100MBps full duplex mode....

sir if you can think of some other pointers than kindly reply me back..

thanks a lot again sir
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Visitor
Visitor
7,458 Views
Registered: ‎09-05-2013

sir i have not given any specific constraints for the ethernet connections... can this be the reason, but as you correctly pointed led blinking has nothing to do with fpga configuraton initially

 

also my software and fpga design worked for altys boars so i do not have any doubt in this side, but wanted to confirm.... 

 

kindly guide....

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Visitor
Visitor
3,261 Views
Registered: ‎09-05-2013

dear all,

 

i have gone for refabrication of my board but still i am facing the same problem i.e no link leds glowing when i connect UTP cable to the RJ45 port.

 

I have also corrected the pin swapping error in the new board which i have also mentioned in my earlier posts...

 

any pointers are highly appreciated and very much required

 

 

regards

aditya

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Teacher
Teacher
3,252 Views
Registered: ‎03-31-2012

did you measure the led pins directly with a voltmeter? maybe the leds are mounted incorrectly.
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Visitor
Visitor
2,286 Views
Registered: ‎02-14-2010

Hi,

 

Watch out RJ45 connections!! 

 

This schematic is wrong.

 

According to your schematics you have to do this changes (asuming you are using HFJ11-1G01E  magnetics...):

 


RJ45 pin   change to     PCB pin 
  6   -------------------------->    4
  4   -------------------------->    5
  5   -------------------------->    2

 

Regards

Julio

 

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