Keypad Passcode

Projects Programming
1

Hey y'all,

I have an Arduino Uno and a 13 pin, 12 digit keypad(1234567890#). I'd like to make a security system with a four digit passcode. # is used to arm the system. I figure if I mount it in a box with a bread board and I jumper all the digits that are not part of the four digit code together and call them the wrong digits, as a whole. I route them to a single input on the Arduino. The four digits used in the code each get routed into there own pin. Say my passcode is 4231. 4, 2, 3, and 1 each get there own input. 567890 all get stuck together into one input. I need to program it so that if I press 4231 in that order and don't press any wrong digits in between, it sets a variable to disarmed. Then, pressing # resets it to armed. I can set off alarms, and check sensors while armed. Any suggestions as to how I go about programming? I don't know where to start.

Thanks in advance.

2

You would be better off connecting the whole keypad as a working device, and leave the processing for software. This library may help;

http://arduino.cc/playground/Code/Keypad

3

The book Arduino Evil Genius http://www.arduinoevilgenius.com/ Project 27 is very similar to what you are talking about. You can download the example code on their site. I did the same thing, but I didn't have a keypad, so I used a soft pot.