?
The next step is to check the power cable which you are using for continuity. If you don't have an
ohm meter, try using a different power cable, if this does not
help try using a different power supply.
?
The last step will be to check the
Power / Data Connector
on the GLK12232-25. If the
Power / Data
Connector
has become loose, or you are unable to resolve the issue, please contact Matrix Orbital
see
16.5 on page 61
for contact information.
3.2 The display module is not communicating.
?
First, check the communication cable for continuity. If you
don't have an ohm meter, try using a
different communication cable. If you are using a PC try using a different Com port.
?
Second, please ensure that the display module is set to communicate on the protocol that you are
using, by checking the
Protocol Select Jumpers.
To change the protocol used by the display module
see
Section 2.4 on page 9.
?
Third, ensure that the host system and display module are both communicating on the same baud rate.
The default baud rate for the display module is 19200 bps.
?
If you are communicating to the display via I2C please ensure that the data is being sent to the correct
address. The default slave address for the display module is
0x50.
NOTE
I2C communication will always require pull up resistors.
?
Finally, you may reset the display to it's default settings using the
Manual Override Jumper, see
Section 2.6 on page 11.
3.3 The display module is communicating, however text cannot
be displayed.
?
The cause of this is often that no font has been loaded onto the
display. To load a font onto the display
see
Section 4.2.1
?
Another common cause may be that the contrast settings have been set to low. The solution to this
problem is to adjust the contrast settings, the default setting that will work in most environments is
128.
NOTE
Optimal contrast settings may vary according to factors such as temperature, view-
ing angle and lighting conditions.
3.4 There is a problem uploading fonts or bitmaps.
?
First, ensure that you can communicate to the display. A good
test is to use a PC, with MOGD# in-
stalled, to connect to the display. See
Section 1.4 on page 4
for setting up a PC to test the GLK12232-
25.
?
Second, ensure that the
File System Lock Jumper
has not been set. See
Section 2.5 on page 10.
Matrix Orbital GLK12232-25
13