SPI Master - Slave sample under zephyr

RE: SPI Master - Slave sample under zephyr

dejans — Thu, 10 Feb 2022 17:17:03 GMT

Hi Bob,

Please take a look at samples and this spi slave case.

Best regards,
Dejan

RE: SPI Master - Slave sample under zephyr

BvdP4Celsius — Thu, 10 Feb 2022 09:17:28 GMT

Thanks for your reply.

However, it is still not working for me.
I try to start an receive action as soon as I see the chip select pin become active.
The chip select pin (cs_active) is set by a GPIO interrupt and connected to a RPY acting as the SPI master.

void spi_slave_task(void)
{
    for( ; ; )
    {
        if(cs_active)
        {
            printk("chipselect_low detected\n"); 
            int rets = spi_transceive(spi1,&spi1_cfg,&txs,&rxs);
            LOG_INF("spi_transceive, slave mode reported %d",rets);
            if(rets > 0)
            {
                printk("Received: 0x%02X 0x%02X 0x%02X-- \n", spi1_rx_buffer[0],spi1_rx_buffer[1],spi1_rx_buffer[2]); 
            }
            cs_active = 0;
        }
        k_msleep(1);
    }
}

Is there any SPI slave example available? The only examples I found are SPI master.
Regards,
Bob

RE: SPI Master - Slave sample under zephyr

dejans — Wed, 09 Feb 2022 18:34:23 GMT

Hi,

Based on the definitions found in zephyr\include\drivers\spi.h, you would need to make a change to your code

struct spi_buf bufsm_r =
{
.buf = spi0_rx_buffer,
.len = SPI_BUFFER_SIZE
};

Best regards,
Dejan