OLIMEX© 2015
MOD-RGB firmware note
MOD-RGB is a completely open-source module suitable for controlling multicolor RGB LED
strips. The strips can be either 3.3V, 5V or 12V powered. The board comes with custom open-
source firmware to simplify the usage of the board. The custom firmware also makes it possible to
communicate with the board via I2C. As an alternative to the I2C the board has also a DMX
interface. More information for how the firmware source code was compiled might be found in the
"project_information.txt" file inside the source code folders (the source code of the latest firmware
is available at the product page of MOD-RGB). The latest firmware version is release 3. Different
firmware revisions might have big differences and incompatibilities.
The LED strips should have three separate data lines for each color – RED, GREEN and BLUE.
The LED we used also had a separate power supply line.
The OLIMEX strips named LED-STRIPE-XX and LED-ROPE-XX work without the need of
MOD-RGB.
The LED strips used with the board might be of the same color or different colors. The board has
short-circuit protection and can provide up to 5A to each strip channel. Olimex provides Arduino
examples for interfacing with MOD-RGB.
Sample hardware connection between an UEXT board (OLIMEXINO-STM32), MOD-RGB, and a
suitable LED strip (3-color 12V) can be found in the picture below:
Note that the picture shows RGB that requires 12V DC provided to the PWR_CON connector. Pin 1
is 12V, pin 2 is GND. In this case UPWR_E jumper should be open by default.
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