Reading The Keypad Illustration

This illustration demonstrates the whole process involved in reading the keypad. First select the key(s) to be 'held down' by clicking on the appropriate key's image. Clicking the image again will deselect it. Then click on the 'Next Step' button below to cycle through the process of reading the keypad. The text below the 'Next Step' button explains the result of each stage.

Keypad Top Upper Nibble Of A Register
Keypad Top
Keypad Left / * ( ) Keypad Right

7 8 9 -

4 5 6 +

1 2 3 Enter

0 .
Keypad Bottom
Indicates comms to the keypad has been established
Indicates comms to the keypad has been established
Indicates comms to the keypad has been established
Indicates comms to the keypad has been established
Unique Key Code:
00h
ROW2 / ROW1 (5B89h)
00h
FLAGS / ROW3 (5B88h)
C0h
ROW4 / ROW5 (5B8Ah)
00h