IR Board Problems

[kylelanman]

Once again an IR board has been fried. I do realize there are multiple threads like this. My question is what rule says that we have to use there ir board and we can't build our own. Seeing as how they won't sell a replacement and multiple teams have the problem can we build our own??? The board would read four commands and output 4 digital outputs. I'm not trying to do anything sneaky I just need an IR board.

[pheadxdll]

There is nothing against the rules to make your own IR board. Go for it!

[dlavery]

You can build your own IR receiver board. You can also buy a different IR receiver board from any of a number of commercial sources (there are lots of them available with similar functionality). You can also use a completely different signaling technology. The IR boards provided in the Kit Of Parts are optional items - there is nothing that says you have to use them.

-dave



.

[Tom Line]

Dave, can you perhaps give us a nudge in the right direction for a commercially available board? I spent 30 minutes googling for programmable IR boards with digital outputs and didn't come up with anything even resembling what we're using.

[Kevin Watson]

Originally Posted by Tom Line

Dave, can you perhaps give us a nudge in the right direction for a commercially available board? I spent 30 minutes googling for programmable IR boards with digital outputs and didn't come up with anything even resembling what we're using.

Here are some random thoughts on this issue.

1) Doing a little reverse engineering on the IR board code, it looks like the brown out reset bit has not been set within the PIC16F87 design, which could be a problem. If there is interest, I could provide a modified hex file with this bit set. You'd need to buy or make a PIC programmer.

2) Back in 2004, I developed the infrared beacon system for FIRST. With a little bit of code and a $1 Vishay IR sensor, you could turn your robot controller into the IR receiver. The 2004 code and documentation can be found here. Of course, if teams want to standardize on one protocol, I'd be happy to provide some sample code.

-Kevin

[marccenter]

Originally Posted by Kevin Watson

Here are some random thoughts on this issue.

1) Doing a little reverse engineering on the IR board code, it looks like the brown out reset bit has not been set within the PIC16F87 design, which could be a problem. If there is interest, I could provide a modified hex file with this bit set. You'd need to buy or make a PIC programmer.

-Kevin

Kevin,
If you make this available, and I figure out how to make a PIC progamming cable , (I have a new, Microchip ICD2 system), I will try the software in one of our IR boards.

[Kevin Watson]

Originally Posted by marccenter

Kevin,
If you make this available, and I figure out how to make a PIC progamming cable , (I have a new, Microchip ICD2 system), I will try the software in one of our IR boards.

The change looks to be pretty easy. Open up the hex file with a text editor like notepad, go to the end of the file and change this line:

:02400E00101F81

to look like this:

:02400E00501F41

As I don't have an IR board, can someone try this out and report back? Better yet, can someone with a programmer run both versions while lowering the input voltage slowly to zero volts and report the results?

-Kevin

[Frank Neuperger]

REvised to flag the 3 error blinks method of training as an error.

See more detailed post here: http://www.chiefdelphi.com/forums/sh...light=major+IR


I spent part of the afternoon at Microchip in Chandler with a couple super FAE's resurrecting our IR board. It was like being at the Mayo Clinic for uControllers.

TEam 39 had tried the WinPIC freeware and the serial cable with resistors scheme yesterday and managed to erase the chip and then successfully program all but 3 memory locations correctly (many times). We basically rendered the chip totally non responsive. This serial cable "bit banging" programmer scheme may have worked for some teams with success but among other things, it depends a lot on the RS232 voltages from the PC being "just right". These voltages vary from 5 to 12V from Lap top to Desktops and everywhere in between.

At Microchip We used MPLAB IDE and an IDC2 type programmer that is part of the PICkit II progrmming kit. Very easy to do. Nice because it uses the familiar MPlab. MPlab will show you the assembly languge code that corresponds to the hex code for the IR. You could tweak the code if you like!!!

http://www.newark.com/jsp/search/pro...FC-GB100000001

After reprogramming, we found that the IR board perfomed just as unreliably as it did prior to the first reprogramming with the freeware. We could not get through the training of all 4 LED's without an error. After much trial and error we discovered that it trains real well if you hold down the key on the remote untill the 3rd flash of the error light. Wow , what a difference. I wish we knew this little detail at the start of all of this. REVISED: Even though thsi resulted in a tained IR board, it is likely we had the wroing frequency on the REMOTE. After reprogramming remote to a 38 kHz code, we did not see any error lights during training.

If you are getting the error light to blink on power up but have not been able to train, I suggest that you try the "realase on 3rd blink" method above. The error light blinks at power up because the chip is working and the code is executing.

FYI, we used an RCA universal remote (from Walmart) and programmed with code 1001 which is a Sony remote. This is a 38 KHz code.

As some background, when we were still in the desparate mode, we had built an IR detector (phototransitor) and actually verified that the IR remote were using was producing 38kHz pulses. With a box full of remotes collected from households, only a few were 38 kHz. Note that 36 and 40kHz remotes will train the unit but range will be limmited.

Alternate IR's are mostly DIY circuit diagrams. In my searching for over an hour, I found no USA source.

Note that you can replace the chip if you are careful. Use tweezers and a heat gun if you do not have a surface mount rework station. Kill the heat as soon as the chip is free. Let it cool if you have made an usucessfull attempt and then retry. It is not a fine ptich part so a thin tip soldering iron can be used to solder in the new part. heat gun will work too ....if you have done this before.

Get the PIC16LS87 chip here for $5.

http://parts.digikey.com/1/parts/561...lf87-i-so.html

The L means that it can operate 2.5 to 5VDC. This makes it more brown out resistant...but not immune. We did turn on the brown out protection bit before reprogramming. This will cause the processor to halt and preven errant execution. It will reset/restart when voltage is back withing spec. nice part ... 5 Mips for $5 !!!

Team 39 will bring a programmer to AZ and Vegas in case a team wants to try to reprogram their chip. We are in Gilbert if you want to do so before the regionals.

This ends a frustrating chapter for Team 39.

Will repost under separate thread for more visibility.

[billbo911]

Originally Posted by Kevin Watson

Here are some random thoughts on this issue.

1) Doing a little reverse engineering on the IR board code, it looks like the brown out reset bit has not been set within the PIC16F87 design, which could be a problem. If there is interest, I could provide a modified hex file with this bit set. You'd need to buy or make a PIC programmer.

2) Back in 2004, I developed the infrared beacon system for FIRST. With a little bit of code and a $1 Vishay IR sensor, you could turn your robot controller into the IR receiver. The 2004 code and documentation can be found here. Of course, if teams want to standardize on one protocol, I'd be happy to provide some sample code.

-Kevin

Even if we don't use code like this for this years competition, I would love to put together a IR controlled Vex project. Please, feel free to build and/or modify code to make a controller into an IR receiver, I'm certain I can port it to Vex.
I will take a look at you 2004 code and see what I can come up with based on what you already have.

[Kevin Watson]

Originally Posted by billbo911

Even if we don't use code like this for this years competition, I would love to put together a IR controlled Vex project. Please, feel free to build and/or modify code to make a controller into an IR receiver, I'm certain I can port it to Vex.

I'm working on code that will work with the 12-bit Sony protocol.

Edit: Here's the FAQ that I started, but quickly forgot about: http://www.kevin.org/frc/2004/faq.htm

These photos showing how to quickly and cheaply build a sensor unit might be of interest: http://www.kevin.org/frc/2004/tracker

-Kevin

[billbo911]

Originally Posted by Kevin Watson

I'm working on code that will work with the 12-bit Sony protocol.

Edit: Here's the FAQ that I started, but quickly forgot about: http://www.kevin.org/frc/2004/faq.htm

These photos showing how to quickly and cheaply build a sensor unit might be of interest: http://www.kevin.org/frc/2004/tracker

-Kevin

Kevin,
Thanks for the links. I actually looked at those documents yesterday directly on your webpage. My mind started racing with the possibilities. It looks like I have a new project that I will start working on once robotics season is over (does robotics ever and?). I am just hesitant to start a new project that will take my focus away from where it should be.
One of the simplest ideas I'd like to try is making a vex robot that follows around our big robot just for the fun of it, kind of like a little puppy dog.
Wherever the big robot goes, the little one follows, all by following the infrared beacons. I also considered using the IR beacon as a way to communicate PWM values to drive the slave (Vex) robot as well. Again my mind is racing with the possibilities.
Thanks again for all the work you have done so far and am looking forward to see what you have next.

[NOV8R]

Dave Lavery in an earlier post stated

"You can build your own IR receiver board. You can also buy a different IR receiver board from any of a number of commercial sources (there are lots of them available with similar functionality). You can also use a completely different signaling technology. The IR boards provided in the Kit Of Parts are optional items - there is nothing that says you have to use them."

I've posted a Q&A question asking if he's correct " You can use a completely different signaling technology" If yes, I also asked if we can use 2.4 Ghz spread spectrum. I fly large scale radio controlled airplanes using this technolgy and it has none of the shortcoming of IR. We'll see what the Q&A folks have to say.

[Vikesrock]

Originally Posted by NOV8R

Dave Lavery in an earlier post stated

"You can build your own IR receiver board. You can also buy a different IR receiver board from any of a number of commercial sources (there are lots of them available with similar functionality). You can also use a completely different signaling technology. The IR boards provided in the Kit Of Parts are optional items - there is nothing that says you have to use them."

I've posted a Q&A question asking if he's correct " You can use a completely different signaling technology" If yes, I also asked if we can use 2.4 Ghz spread spectrum. I fly large scale radio controlled airplanes using this technolgy and it has none of the shortcoming of IR. We'll see what the Q&A folks have to say.

The answer will almost certainly be no. Allowed communication methods for hybrid signaling according to the rules are IR, Ultrasonic and Visible Light.

Active SIGNALING DEVICES shall:
 use visible light, infrared communications, or sound as the transmission method – no
other form of electro-magnetic radiation is permitted
a. All radio frequency communications (as defined by the United States Federal
Communications Commission) are explicitly prohibited.
b. All laser-based communications by any device classified by the U.S.
Department of Labor Occupational Safety and Health Administration (OSHA)
as a laser are explicitly prohibited.
c. All communications must satisfy Rule <S01>.

[647techangel]

you can make your own as long as you send it with your robot.
then you make it as an "upgrade" part.

[eugenebrooks]

Originally Posted by NOV8R

If yes, I also asked if we can use 2.4 Ghz spread spectrum. I fly large scale radio controlled airplanes using this technolgy and it has none of the shortcoming of IR. We'll see what the Q&A folks have to say.

The rules are clear on this one. We can not use lasers,
and we can not use radio spectrum, as our signalling technology.