Inkey

Syntax

Variable = Inkey

Overview

Scan a keypad and place the returned value into variable

Parameters

Variable is a user defined variable

Example

Dim bVar1 as Byte

bVar1 = Inkey          ' Scan the keypad
DelayMs 50             ' Debounce by waiting 50ms
Print Dec bVar1, " "   ' Display the result on the LCD

Notes

Inkey will return a value between 0 and 16. If no key is pressed, the value returned is 16.

Using a LookUp command, the returned values can be re-arranged to correspond with the legends printed on the keypad: -

bVar1 = Inkey
bKey = LookUp bVar1, [255,1,4,7,"*",2,5,8,0,3,6,9,"#",0,0,0]

The above example is only a demonstration, the values inside the LookUp command will need to be re-arranged for the type of keypad used, and its connection configuration.

Declare for Inkey

Declare Keypad_Port Port Assigns the Port that the keypad is attached to.

The keypad routine requires pull-up resistors, therefore, the best Port for this device is PORTB, which comes equipped with internal pull-ups. If the Declare is not used in the program, then

PORTB is the default

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