Matrix Orbital LK202-25 - Manual (Page 13)

9
Power Through DB9 Jumper
In order to provide power through pin 9 of the DB-9 Connector you must connect the Power Through
DB-9 Jumper labelled D, as illustrated below. This connection can be made using a zero ohm resistor,
recommended size 0603, or a solder bridge. The LK202-25/VK202-25 allows all voltage models to use
the power through DB-9 option, see the Voltage Specifications for power requirements.
Figure 11: Power Through DB9 Jumper
Protocol Select Jumpers
The Protocol Select Jumpers provide the means necessary to toggle the LK202-25/VK202-25 between
RS-232, TTL and I²C protocols. As a default, the jumpers are set to RS-232 mode with solder jumps on
the RS232 jumpers. In order to place the display module in I²C mode you must first remove the solder
jumps from the RS232 jumpers and then place them on the I
2
C jumpers. The display will now be in I²C
mode and have a default slave address of 80, unless changed with the appropriate command. Similarly,
in order to change the display to TTL mode, simply remove the zero ohm resistors from the RS232 or I²C
jumpers and solder them to the TTL jumpers.