Hack old vending machine touch pad to control LED lights

Mike,

These switches are usually connected as a matrix of rows and columns, with the switches connected between them.  Like this:

Using an ohm meter, connected between a column and a row, press the switches until you see a low ohm reading.  Just guessing from the image of the pad/connector, that the three pins towards the right might be the columns and 7 or the 8 pins to the left might be the rows.

Hopefully this will help you get started.

Good Luck!

Gene

that's a great start. 

For the Ohm meter to work, do i need to connect the controller to a power source?

so, ill need a power supply (transformer). This will connect to some sort of receiver.  The receiver that connects to the transformer and to the LED strip and the controller.  The controller will send a signal to the receiver to let the LED strips know what color and lights to use.

the only receivers i see online are only for wireless connections, do you know of any wired receivers that could possibly take a 12 pin connection?

No power needed - the resistance meter has its own power. It is not a good idea to measure resistance with power on the controller as it can overload the meter.

thanks!!

Mike,

This switch pad will most likely connect to a controller of some sort.  You are not likely to find a controller that will directly interface to this switch pad and control the lights in the exact way that you would like.  I would think that something like an Arduino would make an excellent starting point.  The controller will read the switches and according to a program, take appropriate actions based on the program that you write.  There are many great examples on Ardunio based projects on this site that you can look at to get an idea of what might be involved.

Using an ohmmeter (https://www.newark.com/velleman-sa/dvm850bl/compact-dmm-with-backlit-display/dp/88C3438  for example) you can map out the rows and columns of the matrix and determine where in the matrix each switch is connected.  This will necessary so you can program the Ardunio how to determine which switch is being pressed, and how to respond to that switch press.  To do this, start by attaching on lead of the meter to one of the pins on the connector (I would try on of the pins to the right of the connector).  Attach the other to another pin (one of the pins to the left of the connector).  The meter should read a high resistance (open).  Now start pressing buttons until the meter reads a low resistance (switch closed). Write down the two pins and the button that was found to make a connection.  Now, change the lead on the left side of the connector to another pin (still on the left side) and repeat the process.  After finding seven switches, change the other lead (on the right side of the connector to another pin).

It is not going to be some magical, plug and play experience.  You will need to put a lot of pieces together in order to make your creation come to life.  But in the end, you will have learn a lot and also have a very unique creation of your own making.

Have fun, good luck and never stop asking questions or learning new things.

Gene

I recall lorrainbow demonstrating working out a keypad matrix in one of her videos:

#badass Woman Project Entry - Lorraine Underwood

May be of interest.

this is great information, thanks!  So i first just map out what each pin does (what button it controls), then i can program the arduino to tell the LED lights how to respond?

I'm guessing that the ardunio has 14 digital connections, i can use 12 from the key pad and 2 to the LED lights

This is great because i have so many projects/art pieces i want to attempt.

a year ago, i started renovating a 6000 sq foot run down space used by drug addicts.  I didn't know a thing about electricity or plumbing or basic carpentry.  I had to teach myself everything.

i will look at it now