Skip to main content

GPIO testing



Since the environment of the client-server-target is currently quite functional in the messaging standpoint, I decided to try connecting a simple LED light to the Raspberry Pi to see if it could "open" a door when the command is received.

Installed the RPi.GPIO module (a Python module that gives the user command of the GPIO--General-Purpose Input/Output--ports in the Raspberry Pi) and connected the LED light to a GPIO pin. When the target received a request message, it would signal the GPIO pin to drive a current to the LED to light it up for 2 seconds.

in main:
if __name__ == "__main__":
  GPIO.setmode(GPIO.BCM)
  GPIO.setup(17, GPIO.OUT)

in the on_message's request-received logic:
     GPIO.output(17, True)
     time.sleep(2)
     GPIO.output(17, False)


The video is a weak visual result. You can a click when the LED lights up; that was the sound of the key being pressed that sent the request message.

Now, time to get (think up of ) some actuators that can do what I want to do.

Comments

Popular posts from this blog

nodejs migration

Having been playing around with NodeJS recently,  I (naturally?) started re-writing some of the OpenSesame code using Node last night. I think I've only worked on it around 2 hours so far, but I've already set up a basic client interface (a socket.io chat tutorial rip) with a server that the Raspberry Pi can connect to and receive requests to open the door.  This is probably due to socket.io's socket management (socket.io is the WebSocket module for Node); for my first implementation, I had to manually write up a structure that managed sockets, but that is pretty much handled by socket.io. Also, the servo control logic is pretty much recycled (and the Raspberry Pi code is still Python), and I do remember spending some good time figuring that out.  Cool neverthelss. I'll probably keep both versions around.

quick recollection on setting things up

If I can swear that the password is correct, then it's possible that I'm getting the ID wrong. Hadn't logged into the web server in a couple of months and was unable to SSH into it. After an hour or so, I ended up deleting the instance and recreating a clean instance (read: erasing everything). I then realized I'd been putting the wrong ID.   apt-get install sudo apt-get install Anyways, some links I visited when setting things up (pretty much a dump of whatever I copy-pasted to notes) : Raspberry Pi http://www.makeuseof.com/tag/optimize-the-power-of-your-raspberry-pi-with-raspbian/ Logging http://docs.python.org/2/howto/logging-cookbook.html Tornado - Python webserver that supports Websocket http://stackoverflow.com/questions/2924991/what-popular-webservers-have-support-for-html5-websocket http://lowpowerlab.com/blog/2013/01/17/raspberrypi-websockets-with-python-tornado/ http://stackoverflow.com/questions/11695375/tornado-identify-tra...

alcohol sensor (and some patience)

Soldered the alcohol sensor into something that is connectable: I tried to connect this to the Arduino, as I had the appropriate circuitry, but I did not get any legitimate output from it. 5V going in, 5V coming out with no variations. Nothing seems to be awry in wiring, as the circuit seems to be grounded properly (and the 5V current is flowing).  There are a couple of potential factors as to why I'm not seeing any results: - I'm using a 10k ohm resistor, while some guides (and the datasheet for the sensor) asks for 100-200k. However, there seems to be a good amount of people using 10k and getting at least some kind of result. A batch of 100k ohm resistors I ordered is on its way, so I guess I can try with them when they come. - This site  claims that these sensors take 24-48 hours for its signals to be stable. It also tells me that I should not be powering the sensor directly from the Arduino, which I have been doing, out of concern that the power draw of ...