Problem following YBOX2 Kit construction

[AlaskaRay]

I've completed the kit and find that I get the appropriate video image (and a green LED) at each step until I place the ENC28J60 chip in it's socket, then nothing happens. I've checked all my connections and solder joints and cannot find the problem. I've traced every connection from the schematic. I am not a novice at building curcuits and can usually find the problem, when there is one, but not this time. I'm wondering if the chip is defective. I have a logic probe, but I'm not sure how to check this chip. Please help. Thanks.

[adafruit]

when you say nothing happens...can you be more specific about what it is you're expecting it to do?

[AlaskaRay]

I'm expecting there to be something on the monitor besides blackness. Without the ethernet chip I get the appropriate message on the screen, but once I install it and power up the unit, there is nothing on the screen.

Since my original message I have again double checked component placement (all correct) and examined the PC board for breaks (none) and all the solder joints (all fine) under a microscope. I've also checked the crystal (cycling) and used a logic probe to check the ethernet chip. Even though I found a schematic of the chip on the manufacturer's website, it's hard to know what state each pin should be, however, I was able to determine that it's receiving power and that it's internal clock is not cycling. Based on that I have to assume it's a bad chip, but I'm not sure. I may call ThinkGeek tomorrow for their input, but any help here would be appreciated.

Thanks.

[adafruit]

thinkgeek will be utterly unable to help you, they're just resellers
im a bit surprised that inserting the ethernet chip would make it wonk out. are you sure none of the pins are bent? its in right? are you using a good power supply that can provide enough current?

[AlaskaRay]

Thanks for the response. I'm always careful with the pins, but one of the first things I did was to double check that all the pins of all the ICs were properly inserted. I use a good variable power supply for all my small projects. I double checked it's output and it's set for 7 V and up to 1 A (which I confimed with a VOM). I was going to call ThinkGeek in the hope they could supply a replacement chip. My office is only about 2 miles from their office so I could just stop by and drop in the new chip to see if it worked.

Thanks, Ray

[adafruit]

thinkgeek wont be able to help you, they dont have any spare parts or anything. in fact they'll just direct you to me. email support@adafruit.com (as indicated on http://www.ladyada.net/make/ybox2/parts.html)

[AlaskaRay]

Can you supply me with a new chip? I will e-mail you privately with shipping info, if you can.

Thanks, Ray

[darco]

Does the Ethernet chip get hot if you leave it running? Do you know how much current is being drawn? About the only thing I can think of that would cause the prop to stop working like that would be a short circuit.

BTW: the clock for the Ethernet chip is generated by the propeller itself--if the prop isn't booted then the Ethernet chip will have no clock.

[AlaskaRay]

As I mentioned in a previous posting, I've checked the board (both sides) under a microscope (I'm a scientist and have several) looking for anything that might cause a short. I've also checked each solder joint and looked for breaks in the printed circuit.

The ethernet chip acutally has its own clock (accessible at pin 3) though it's not used for this project. As I said, it does not appear to be cycling when checked with a logic probe. The chip gets slightly warm after leaving it plugged in for a while.

As I previously mentioned, with the ethernet chip removed, I get the expected video output and the LED flashes green. That suggests to me that the everything prior to that stage is working correctly. Once I inset the ethernet chip, I get no LED and no video output. I can't tell you how much current the chip is drawing, only that it registers 3 volts at pin 1, which indicates it's getting power.

Thanks, Ray

[darco]

I was actually thinking the short might be in the chip itself.

The clock output on the chip is a suppemental clock output, which is just the input clock divided by a software-configurable constant. It won't cycle without an input clock, which would be generated by the propeller.

[darco]

I did some more thinking about this, and I have a few hunches. 3volts is a bit low, and the propeller may not be able to operate properly at that voltage. Try bypassing the diode(ie: just solder a temporary wire across it). It's a long shot, but it may work.

[adafruit]

Can you supply me with a new chip? I will e-mail you privately with shipping info, if you can.

Thanks, Ray

email support@adafruit.com (as indicated on http://www.ladyada.net/make/ybox2/parts.html)

[AlaskaRay]

I did some more thinking about this, and I have a few hunches. 3volts is a bit low, and the propeller may not be able to operate properly at that voltage. Try bypassing the diode(ie: just solder a temporary wire across it). It's a long shot, but it may work.

It's actually a hair more than 3 V, which seems correct to me since the voltage regulator chip (LD33V) limits the voltage to 3.3 V. Perhaps you can explain your suggestion further.

Thanks, Ray