Hi I implementen VSPI default pins for read 4 max6675, the cs pins goes across I2C i/o expander pca9555, and have another pca9555 for inputs.
All goes flow fine, 70ms delay max fron host but....
Some times lag 1 or 2 seconds. I fees is the SPI doesn't not catch the 16 bits and keep waiting for it.
I cant found time Out of SPI lib for transfer 16b.
Some body have a similar experience?
Some body can implement the spi with dma on arduino?
Thanks