Matrix Orbital PK162-12 - Manual (Page 7)

1.5 Trying Out the PK162-12
The unit should be connected to power and the PC and backlight should be on.
To experiment with typing text, run a PC terminal program such as Hyperterm.
Make sure it’s configured to use the correct port. Set the baud rate to 19,200.
If characters are typed on the keyboard, they should now appear on the display screen. Text will wrap
around to the next line when the end of a line has been reached.
1.6 Trying out a Keypad
Since a number of different keypad types can be connected to the display, the results may be a little
unpredictable. At this point all we need to do is make sure that the keypad and interface work, and possibly
generate an ASCII map for any programming needs. The keypad interface on the display converts a row /
column connection to an ASCII character. By default, a keypress is transmitted as serial data immediately.
Keypad buffering can be selected using the appropriate commands.
1.6.1 Here’s what to do:
1. The PC should be running a terminal program, such as Hyperterm, as in the previous section.
2. With the display connected to the PC, plug the keypad in. If the connector has fewer pins than the one
on the display, center it as well as possible.
NOTES
• The keypad connector must be wired with columns on one side and rows on the other
side of the center of the connector. If the keypad isn’t wired this way an adapter must
be made or the connector must be rewired to meet this requirement.
• The connector is reversible. Reversing the connector will not damage the keypad or
the display, but will however, change the ASCII character map.
3. Press a key on the keypad. An upper case ASCII character (A-Y) should appear on the PC screen.
Different keys should generate different characters.
To experiment, reverse the connector and see if it generates a more logical set of characters. Ultimately, the
program in the micro-controller will have to ’map’ these characters to the ones marked on the keypad, which
will likely be different.
1.7 Manual Over-ride
Manual over-ride should only be required in one instance. If for some reason the module is set at a baud
rate which cannot be produced by the host system and all communication to the display is lost, then the user
should follow this simple procedure;
Matrix Orbital PK162-12 3