WiFi IR Remote

[dlevans]

Haha thanks. Glad I could... help? yeah, we'll go with that. My work schedule is a little messed up for the next couple of days but I'll give it a try asap. Did you get my PM with my email?

*edit*
I just got your PM. Guess we were writing at the same time.

[GregEigsti]

I may go with a 555 timer for the 38khz carrier - depends on what I can get out of pin 5 PWM. Time to go grab the oscope

Greg

[dlevans]

Awesome. Hopefully it works. If it does I'll have to get one, too. I don't have an oscope, though.

[dlevans]

Also I just scanned your QR pic. Nice. I tried lol...

[GregEigsti]

Heh, heh, heh! First person to have commented on that. The original was much more nasty

Greg

[dlevans]

Haha awesome.

[GregEigsti]

Its looking good so far. Today I played with the code a bit and got the 38khz PWM IR carrier signal working, added an AND gate to mux the 38khz carrier and data signal and threw in the basics of a TCP WiShield app. I have not added the bulk of the socket code but the device comes online and can be pinged before/after receiving IR commands (this is good!). The IR LED is pretty weak at this point - I have a 100 ohm resistor inline and will likely cut that down - I'm sure the fact that it is running off of the 38khz PWM carrier is helping to reduce its brightness. I just don't want to blow it up so will take the resistor down in small steps...

It seems to receive IR just fine but I don't yet have code to do any sort of IR send (this will be an interesting test) - will likely add the send portion as part of the socket code. Need to define some sort of network protocol to spec out what the device should do (e.g. learn, send, store, reboot, version, etc.). Currently its all C but may take the time to go C++ with it and make a nice set of classes, etc. Might also be interesting to use dataflash and/or eeprom to store IR commands for playback.

I sacrificed the connection light on digital pin 9 so that I could use the 16bit timer1 which is more configurable, etc., and provides a nice 38khz PWM for the carrier.

Edit - replaced the 100ohm resistor to the IR LED with a 22ohm and it produced no visible difference. Got the multimeter out and found that I am losing significant voltage in my two transistor AND gate (even at full duty cycle - all on balls to the walls). Voltage at the emitter of the first transistor is 4.8 (running off of USB and matches voltage at Arduino's +5v out). Voltage at first transistor's collector is cut roughly in half. Voltage at collector of second transistor is a measly 1.8v for full duty cycle and .8v for 50% duty cycle. I guess I'll have to do a little research... More efficient transistors (using 2N2222's)? Different circuit? Dunno - I aint not a EE

Anybody have an idea for components/circuit that does not have such a voltage drop? I need to AND together the 38khz PWM generated carrier and a logic pin that specifies the 1's and 0's...

Fun stuff!
Greg

[GregEigsti]

Right now my transistors are in "series" - that is one's collector is connected to the other's emitter. I wonder if I made the circuit more "parallel" so that one's emitter is connected to the other's base if things would be better (could mitigate one transistor's voltage drop as well as the drop implied by the 50% duty cycle). Hmmmmm...

Too many late nights in a row... Gonna sleep on it...

Greg

[dlevans]

Thanks for your help on this. Glad to see things are working for you. I've still been busy with work but i'm off tues/wed. Hope to help then. Also on mine I was thinking about having up to 5 IR LEDs that plug into a box the with arduino. I made one led a quick connect using a headphone jack and a plug. So if you're only controlling one device you only plug in one IR LED. That way the device could sit next to your tv plugged into a 9v power plug and the LEDs could sit right in front of the device it was controlling... provided there are enough PWM ports or ways to get 38Khz without PWM.

[GregEigsti]

All of my gear sits in a rack in a closet in the back of the room - the gloss white closet door is shiny enough to reflect the signal back to all of the gear in the rack (multiple LEDs for a nice blast would be nice though - my rethinking of the AND gate should make this possible)... The 38khz carrier should be able to be shared among outputs with the correct circuit (I aint no EE but it sounds doable...) - so you would only need the one PWM output.

Your plan for "remote LEDs" sounds interesting as you could make them addressable - that is your command sent over the network could specify which device to blast with IR rather than blasting them all. I know that my scenario works and know that all of my current gear's IR codes do not conflict so...

Just whipped up a quick python TCP socket client script and can send/receive data to/from the Arduino/WiShield as well as receive IR data from that Radio Shack IR sensor part - repeatedly. So there is still lots left to do but I am closing in on playing the data back via the IR LED.

I'm gonna go out on a limb here and say that the Arduino/WiShield are perfectly capable for this task

Greg