I'm looking into a issue on a Pi with SPI port, to clock continuously and stream data to memory area using a DMA.
The sensor I connected on SPI on a Raspberry Pi 3, should be clocked with more than 3MHz, and has a wake up time on about ~200us, after first clock is send. I would like to record more than 0.5s with continuous clock to the device. If the clock stop the sensor go to sleep mode.
I'm using this spi-driver.
In the SPI driver I found out that 65536 is max size for DMA in the Pi, so I was wondering if it's possible to use two DMA, and let one DMA trigger start of the second and so on.
Any idea if that is possible? Or other solutions how to clock a sensor with more than 3MHz while streaming the data to memory for analyzing it afterwards.