- pentawall ************
This project aims to build a full-RGB LED-wall with a resolution of at least 15x15 pixels.
This is done using stackable 5x1 LED modules. (pentawall because its 5 LEDs per module)
- technical overview *****
each module consists of
- 5 LEDs ( Osram LRTB G6TG )
- 1 LED controller ( Textas Instruments TLC5941 )
- 1 microcontroller ( Atmel ATMEGA168pa )
The TLC5941 is a 16-channel, constant-current sink, LED driver. Here only 15 channels are in use (5 LEDs * 3 colors). Each channel has an individually adjustable 4096-step grayscale PWM brightness control and a 64-step constant-current sink (dot correction). Both grayscale control and dot correction are accessible via a serial interface (SPI). For grayscale control the atmega has to feed in 24 bytes of data (16 * 12 bit).
The microcontroller receives its data via an i2c bus.
the master module recives data via USB and feeds that data to the led modules via i2c bus. Using this master any PC with USB can control the LED wall. If you have i2c on you computer you dont need this module.