nrf5340 SPI configuration problem

RE: nrf5340 SPI configuration problem

user107188 — Mon, 13 Jun 2022 17:01:35 GMT

The problem had been solved. You may close this ticket now.

RE: nrf5340 SPI configuration problem

user107188 — Fri, 11 Mar 2022 22:56:24 GMT

I wrote a sw bitbanging version of SPI driver using GPIO pins and it is faster the Zephyr SPI driver. 62 uS vs 102 uS, so Zephyr SPI has problem. It just can't be slower than sw bitbanging. <---- This is Zephyr SPI. It takes 102 uS. Slower than sw bigbanging using GPIO.

RE: nrf5340 SPI configuration problem

user107188 — Thu, 10 Mar 2022 22:50:33 GMT

Hello Øivind,

The SPI works, but it is a bit slow as indicated by the timing of the signals on the SPI bus. In 101uS between the falling edge and rising edge of CS, almost 60uS waiting time after the slave had finished putting data on the bus. There seems to be room for optimization in Zephyr SPI code.

RE: nrf5340 SPI configuration problem

user81283 — Thu, 10 Mar 2022 14:13:17 GMT

Hi,

The SPI is working without issues now?

RE: nrf5340 SPI configuration problem

user107188 — Thu, 10 Mar 2022 02:37:49 GMT

Get SPI Clock working. No problem at all now.

RE: nrf5340 SPI configuration problem

user107188 — Thu, 10 Mar 2022 02:37:09 GMT

RE: nrf5340 SPI configuration problem

user107188 — Thu, 10 Mar 2022 02:13:38 GMT

Now I get the CS working, but not the SPI clock.

struct spi_cs_control spi_cs = {
	.gpio_dev = NULL,
	.gpio_pin = 14,
	.gpio_dt_flags = GPIO_ACTIVE_LOW,
	.delay = 0,
};

RE: nrf5340 SPI configuration problem

user107188 — Thu, 10 Mar 2022 02:11:27 GMT

RE: nrf5340 SPI configuration problem

user107188 — Wed, 09 Mar 2022 23:19:39 GMT

// CS is pin 14 of GPIO port 1
struct spi_cs_control spi_cs = {
	.gpio_dev = NULL,
	.gpio_pin = 14,
	.gpio_dt_flags = GPIO_ACTIVE_HIGH,
	.delay = 0,
};

// and the spi_cs control is used in the SPI config  .cs = &spi_cs,
static const struct spi_config spi_cfg = {
	.operation = SPI_WORD_SET(8) | SPI_TRANSFER_MSB |
		     SPI_MODE_CPOL | SPI_MODE_CPHA | SPI_OP_MODE_MASTER,
	.frequency = 4000000,
	.slave = 0,
	.cs = &spi_cs,
};


// spi_cs.gpio_dev is initilized in spi_init
static void spi_init(void)
{
    .....
	spi_cs.gpio_dev = device_get_binding("GPIO_1");
	
	.....
	
}



but debugging information shows ss_pin = 255
Something wrong !!!!

RE: nrf5340 SPI configuration problem

user107188 — Wed, 09 Mar 2022 23:03:39 GMT

Dumping debugging information showing the SS_PIN is 255. Something is no right.

RE: nrf5340 SPI configuration problem

user107188 — Wed, 09 Mar 2022 23:00:05 GMT