Re: Problems with IR Board
 

I can not make our board work either. I have tried hooking it up to a 9 volt battery and a benchtop power supply set to 9 volts, and have verified that there are 5 volts across C4 and the pins 2 and 3 on the white connector. However, nothing happens when I connect power. If I hold down the "learn" button and connect the battery, none of the LEDs light.

I've paranoidly double checked the polarity every time I've connected it, and since I have been fairly careful, I doubt static has damaged it (though that is always a possibility.) I seem to attract problems sometimes...

---[More fiddling with the edit window still open]---

Aha! Our board DOES work. Just not the LEDs. I checked across the contacts of the LEDs with my trusty voltmeter after entering the setup sequence, and low and behold CMD0 had 5 volts across it. So I tried going through the whole learning sequence, then held my voltmeter to the connector and saw a voltage jump whenever I pressed the button. It works! Either all of the LEDs are bad, or could it be the LEDs are wired backwards? According to the voltmeter, the positive leads (for all but ERROR) are the ones towards the outside, which is the side of the LED that has the little notch and the larger piece of metal internally. If I'm reading the Wikipedia page correctly, it seems they should be the other way around.

That's something I could fix myself, but following BMW's recommendation I won't attempt it. Good to know ours works except for that though!

Re: Problems with IR Board
 

And about keen101's board:

Did the same with my Fluke, and also got infinite resistance. But if I jammed the leads just right into some of the holes the board had poked in transit, the resistance dropped to about an ohm. So if the board got pushed into the bag while it was on, it very well could have shorted out.

Re: Problems with IR Board
 

Looking at your picture, the part is made by National Semiconductor (thats the funky looking 'N' as the first letter) .

A quick search found a data sheet here ( http://www.national.com/ds/LM/LM78L05.pdf )

While they are ESD sensitive devices, they tend to be rather robust so a little handling should not hurt them very much.

There are a number of things that these little guys dont like:
1: Input power and ground reversed. So watch your polarity when applying power.
2: Voltage on the output being driven higher than the input voltage. This typically only happends with some sort of inductive kick, but ...
3: Applying more than 35 Volts at the input. Some power supplies (especially older ones) may spike when turning on. Check your power supply with an o'scope to see if it spikes (DMMs don't read fast enough).

They can be bought here http://search.digikey.com/scripts/Dk...M78L05ACZNS-ND

Re: Problems with IR Board
 

For what its worth, I contacted Ben at Diversified Systems and asked about testing the board by bypassing the 5 volt regulator and just powering the board via a regulated 5VDC supply connected to pins 2 and 3 of the white connector. He replied that the PIC will smoke at 5.5 volts but it would be a good test of the functionality of the rest of the board to try it at 5VDC. So we broke down and tried it. Same results, nothing seemed to happen at least with the on board LEDs. Ben indicated that Diversified Systems is working with FIRST to determine how best to resolve the problems so I suspect we will all be getting an email blast from FIRST sooner or later on how to repair/replace/order the IR receiver boards. I guess all we can do for now is wait and see.

Ben and Diversified Systems: Thank you again very much for your support of FRC and the very generous donation. We are all looking forward to learning exactly what it is we are supposed to do with these IR boards!

Re: Problems with IR Board
 

so we finnaly got our board today, but all that would light up was the error LED. we followed the directiond word for word, holding the button before powering up, and letting go after more that 2 sec., and had the Error LED do the instructed Flash once or twice, but never had the 0 LED flash to signal the learning loop.

We also had the board sitting on the anti static bag at one point, but seeing how the error LED light, i doubt we fried it.

Does anybody know if this is a board problem or a user problem?

Re: Problems with IR Board
 

I was quoting the values directly from the users guide provided by FIRST. I agree the circuit past the regulator is run off 5 vdc, but the board it's self is powered by >7.2 vdc to 10 vdc. In the users guide it says that it "assumes" the board is powered by 12 vdc.
Either way, the load drawn by circuit when one LED is on should not exceed the ability of the regulator to power the circuit without failing.

If there is a problem with the circuit, FIRST will find it, maybe with the help of some of us, (Remember the Bane-Bot trannies from last year?) and suggest, provide or publish the solution.

Re: Problems with IR Board
 

It appears only <10 of the total qty have had any concerns. I would hold tight to see what is done for any resolution. All of the boards were powered prior to packaging, programming was reserved for teams per the instructions.

BMW

Re: Problems with IR Board
 

I completely agree: IF there really is any kind of problem, I have complete confidence that FIRST and DSI will make it right.

But, WE have to help! By that, I mean this: Unless you are posting a fact, PLEASE label it as an opinion. At the very beginning of the BaneBots issue, there was a LOT of "noise" from people speculating, guessing an just plain writing what they thought was happening, but with little basis in fact. It was not until certain engineering folks started documenting facts using the scientific method (and photographs) that we got to the "root cause" and enabled BaneBots to address it.

Again: Post facts please, not opinion. If you don't know what happened, then just post your factual observations. If you speculate, then label it as such.

Tally so far:
358: LEDs flash during learning. After, either error light or nothing
456: Totally dead, 78L05 has no output
1357: Worked, then 78L05 fried. Maybe anti-static bag?
2144: Board works, LEDs do not light
2199: Error LED lights sometimes, not "0" (learn loop) LED


FYI: Current advice is NOT to repair the board if you suspect an issue, instead report your observations (to FIRST?). The regulator is a 78L05 in the standard TO-93 package, available almost anywhere (even Radio Shack - PM me and I'll mail you one). +5 VDC can be supplie, but the PIC will fry at 5.5, VDC, so try it only if you are really certain of your power supply...

Thanks,
Don

Re: Problems with IR Board
 

Hmmm.....

Says in the data sheet that these regulators have short circuit and thermal protection built in. In other words, given that the power source is within spec, you should not be able to destroy them (no matter what the load). Maybe some were accidently powered up with reverse polarity at some point. I'm leaning toward the explanations in Daniel's list.

Re: Problems with IR Board
 

If anyone is going to modify/fix this board, wouldn't the work have to be done AFTER kickoff?

Re: Problems with IR Board
 

Our team successfully trained the chip today.
All we did was follow the instructions about pressing the buttons.
We were able to light up the LEDs using channel buttons (1-4) on a universal TV remote.

Tally so far:
358: LEDs flash during learning. After, either error light or nothing
456: Totally dead, 78L05 has no output
846: LEDs flash during learning and afterwards when controlled by remote.
1357: Worked, then 78L05 fried. Maybe anti-static bag?
2144: Board works, LEDs do not light
2199: Error LED lights sometimes, not "0" (learn loop) LED

Re: Problems with IR Board
 

Heh. Maybe people should start using the numbers that Don supplied as error numbers.


for example: I had a "1357 error" on Wed. :D


Tally so far:
358: LEDs flash during learning. After, either error light or nothing
456: Totally dead, 78L05 has no output
1357: Worked, then 78L05 fried. Maybe anti-static bag?
2144: Board works, LEDs do not light
2199: Error LED lights sometimes, not "0" (learn loop) LED

............

Then again... maybe not. I don't know if it would help or not. :)

Re: Problems with IR Board
 

Please focus this thread on issues with the board only.
Can be failures, potential ways to kill the board, or just interesting unreported behavior, such as, getting the LEDs into a chase sequence.:)
Let's assume most of the boards operate normally, and we're looking for that 1%.

I added a thread with a poll where we can report that our boards are working great!

Please don't repeat the talley if you haven't added your team to it. Otherwise it just takes up space.
We're looking for added value.

I'd like to avoid a 1500 post chatty thread of who's board works.

Re: Problems with IR Board
 

no offense but did it ever occur to you guys fiddeling with your board hookup that the ribbon cable is the key to successfull opperation????(ie not frying the board)/it is definatly bad about the faulty voltage regulators....i have no idea about our board.

Re: Problems with IR Board
 

Ours was functioning perfectly fine responding as per the pdf guidelines, then some magic smoke came out of the 5v regulator and it now smells funny (this is a mechanical persons diagnosis). So BMW any advice?