i.MXRT1050 LPSPI in slave mode using other gpios as chip select

[mperez1]

Hello there,

I have a custom board and when the design was made the Chip Select for the LPSPI was another different GPIO instead of the assigned for the PCs of the LPSPI. For the master mode in the LPSPI I changed the driver API to write those pins by software.

But the problem is when I'm trying to use the SPI in slave mode. I can´t find any part in the reference manual where an interruption flag could be set in order to emulate the chip select assertion so I can read a new frame. Is there any posibility of enabling the receiving routine by setting a flag in the gpio interrupt?

Thanks in advanced,

Miguel

[mperez1 · Accepted solution]

I found the solution. In the reference manual rev 4, in the 47.3.3.3 Clocked Interface tells you how to configured the LPSPI_PCS input to be always assert. You just have to configure the Peripheral Chip Select Polarity to high and don´t configure the PCS[n] ib the pin muxing.