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Synchronized Output of 3 Spi with stm32f4 Discovery

jamann
Associate II
Posted on September 28, 2015 at 19:32

Synchronized Output of 3 Spi with stm32f4 Discovery

#dma #spi #stm32f4 #discovery
5 REPLIES 5
Posted on September 28, 2015 at 20:47

Going to be hard, can they be slaves driven by a common clock?

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jamann
Associate II
Posted on September 28, 2015 at 21:25

Somehow my initial text was not posted. I thought about SPI1 as master generating the clock and SPI2+3 as slaves. I need to feed a LED RGB Panel. SCK higher then 21Mhz doesn´t work so SDIO is not an option.

Posted on September 29, 2015 at 00:55

People have modulated LED signals using DMA+TIM+GPIO

The forum doesn't like mobile (tablet/phone) devices, and one wonders why Microsoft has such a time entering those markets. 

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jamann
Associate II
Posted on September 29, 2015 at 08:13

Thank god I don´t have a microsoft phone.

Thanks for the hint. I can try DMA with GPIO

I currently use 1 SPI with DMA to drive all 3 colors daisy chained which is too slow.

I can split up the colors in 6 or maybe even 12 segments with each of them connected

to a single pin. Do you think with DMA transfer and GPIO things will go faster ?

I need at least a speedup of 4 times to achieve to get the framerate I need for 16 shades.

Posted on September 29, 2015 at 08:44

Have you looked at the F429I, it's got hardware for clocking video data.

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