chipKIT Network Shield Not Working...

Created Tue, 15 Nov 2011 07:17:42 +0000 by Jacob Christ

Jacob Christ

Tue, 15 Nov 2011 07:17:42 +0000

So, I've just started playing with my Network Shield and had the WebServer up and running for a few days. Then between power cycles (and removing and replacing the shield from the Max32) the shield stopped working. The Max32 seems okay.

When a network cable is plugged in the LED's on the magnetics no longer light. The port on my hub is good for it works with other boards.

I suspect that one of the boards may be damaged from plugging and unplugging the shield. The boards flex quite a bit during separation and I can't imagine that is good for traces or solder joints.

I can see the 50MHz EREFCLK but the amplitude is quite low (1.5Vpp) and it has about 2V bias above ground (which can't be good). But because I can see the 50MHz signal I'm assuming that the crystal is still good.

The shield has a solid GND, 3.3V and 5V connections measured at the header on the Shield.

I tried to reflow the PHY thinking that the ground lug may not be well soldered but that didn't make any difference. If I don't get any suggestions here, I'll probably take the PHY off and remount it or replace it all together. I don't have the means to x-ray the PHY but usually I can get a good feel for how well it was soldered when I remove parts with hot air.

Jacob

KeithV

Tue, 15 Nov 2011 17:34:59 +0000

Jacob,

I would probably just simply ring out the Network sheild first before unsoldering things first.

In particular, the enable for the PHY is RE9, simply put a volt meter between gnd (J17-gnd) and where RE9 comes out to enable the PHY (J11-15, which on the network shied is labled as Arduino pin 7). Looking at the board this is J11 top right pin labled as 7. It should have 3.2-3.3 volts when enabled, close to zero when not and somewhere around .4-.5 in a tri-state depending on your meter. If this pin is enabled the network LEDs should come ON. Since you are not seeing this, this may be your problem.

Below is a simple sketch to toggle the pin.

KeithV Digilent

void setup() { // put your setup code here, to run once:

pinMode(7,OUTPUT); digitalWrite(7, HIGH);

delay(5000); digitalWrite(7,LOW);

}

void loop() { // put your main code here, to run repeatedly:

}

Jacob Christ

Thu, 17 Nov 2011 23:14:59 +0000

Keith,

Your a genius...

I probed the RE9 pin and indeed it was low so I tried your ringing program (in a loop so that I could see the line going low and high) and the lights on the magnetics indeed turned on and off as the with the nRST line (RE9). So knowing that software doesn't break I assumed that I had loaded the wrong program and indeed I had. I was using the Ethernet->WebServer and not the ChipKITEthernet->WebServer.

Also, another tell tail was the Ethernet->WebServer has the default IP address 192.168.1.177 and the ChipKITEthernet->WebServer has the IP address 192.168.1.190.

Thanks,

Jacob

KeithV

Fri, 18 Nov 2011 18:45:24 +0000

I just hate that when I load the wrong program :D

Glad you got it to work!

KeithV Digilent

KM6VV

Fri, 18 Nov 2011 22:56:33 +0000

That's funny, I can't see the SMSC LAN8720 10/100 Ethernet PHY on the board!

Alan KM6VV

Jacob Christ

Fri, 18 Nov 2011 23:07:23 +0000

Its on the bottom side.

KM6VV

Fri, 18 Nov 2011 23:30:15 +0000

That would explain it!

Thanks,

Alan KM6VV