Calculator
Part List
Arduino Duemilanove
4X3 matrix keypad
LCD from DFROBOT
A sip array resistors (or 4 resistors) is pull up resistors connected to row pins of keypad with the common terminal connected to +5V
Connections
LCD DFROBOT
LCD RS pin to digital pin 9
LCD R/W pin to ground
4x3 matrix key pad
colums pin out of key pad to digital pins 13, 12, 11
sip array resistors
Project ready
is a arduino calculator with Arduino Duemilanove ,
a LCD from DFrobot and A 4x3 keypad matrix
the calculator precision is two decimal points
the * key select the operation you want
= ,+,-,*,/,decimal point,clear memory
the # key is the enter key