First, I finished the PCB for the STM32 board.
Then, for our project, we have chosen the general architecture: the board embedded on the propeller will contains a cortex A8 and a FPGA. Indeed, benchmarks I have found about ffmpeg, the library we will use to convert MPGE2 (or MPEG 4) received thanks to the wifi connection use about 80 % of a A8 cortex. The wifi will use about 5%. So, we can not use the A8 cortex to command the LED drivers.
The question is the following: we can chose working with a armadeus (http://www.armadeus.com/english/products-processor_boards-apf51.html) but we have to design a main board with wifi and, we will only begin to work when the main board will be ready or, we can use a gumstix (the same that we used for previous test) and we have to chose the FPGA and to design the main board with the FPGA but, we can start working on the gumstix now.
Finally, I think about the LED driver we have to use and, the LED board architecture. We decided to use 8 different bus to command the LED driver so, LED will be divided in 3 groups on each propeller. The frequency needed is about 10 MHz for each LED driver. The LED will be command with a PWM signal created by the LED driver.. A LED will have a frequency of about 15 kHz so a PWM frequence of 33 MHz will allow us to chose correctly the LED intensity.
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