Hi,
I have a 4*4 matrix keypad. I want to interface this with VC5505 chip. Right now i have been able to interface 8*2 Oriole alphanumeric LCD with the DSP. I want to program the keypad in such a way that CD will display the key pressed on the LCD.
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Hi,
I have a 4*4 matrix keypad. I want to interface this with VC5505 chip. Right now i have been able to interface 8*2 Oriole alphanumeric LCD with the DSP. I want to program the keypad in such a way that CD will display the key pressed on the LCD.
This keypad is not a standard one you are talking about. I have a 4X4 keypad which has buttons 1,2....10,A,B,...F. How can I interface this keypad? It has 8 pins corresponding to each row and column. Each button is like a mechanical switch which when pressed an electrical connection is established between the corresponding row and column. Should I connect this 8 pins to the GPIO pins of the DSP? Do you have any sample code to program such keypad?
If you have 8 spare GPIO pins, just use them for the keypad in a scanning style. Otherwise, you need to add a resistor array to the keypad and use SAR to read voltage levels.
Do you have any program to read the values of key pressed in key pad? Where does the value of key get stored in DSP? If i connect LCD to the GPIO pins then what resistance value should I use? Then where should I connect the pins?