Hello Nordic Forums.
I have been struggling for the past couple of days to try to get the SPI working. I never thought that something this easy could have become such a nightmare.
I tried compiling and running sample test from Lesson 5 of the Intermediate course (SPI). The problem with the sample is that I always get back 0xFF when I read back from the registry.
I have a bmp390 and I'd be very happy to read back a nice 0x60 value from chip id (registry 0x00), but so far all I was able to read is 0xFF, as you can see from the trace below.
This video shows something very similar to the sample files
https://www.youtube.com/watch?v=zStXcr2Fi44
I tried to write the same code and still get 0xFF. I tried to send a read 0x80 after the registry but nothing worked.
During this painful investigation, I found that for some reasons i am not even able to control some pins (ie pin 9) on the dk.
From the board configuration:
spi1_default: spi1_default {
group1 {
psels = <NRF_PSEL(SPIM_SCK, 0, 31)>,
<NRF_PSEL(SPIM_MOSI, 0, 30)>,
<NRF_PSEL(SPIM_MISO, 0, 29)>;
};
};
While my overlay files is:
&gpio0 {
status = "okay";
};
&gpiote0 {
status = "okay";
};
&spi1 {
compatible = "nordic,nrf-spi";
status = "okay";
};
/ {
cs_one_pin: cs-one-pin {
compatible = "nordic,gpio-pins";
gpios = <&gpio0 11 GPIO_ACTIVE_LOW>;
status = "okay";
};
};
Here is my main.c file
#include <stdio.h>
#include <zephyr/kernel.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/drivers/spi.h>
#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#define SLEEP_TIME_MS 1000
#define LED0_NODE DT_ALIAS(led0)
#define SPI1_NODE DT_NODELABEL(spi1)
static const struct device *spi1_dev = DEVICE_DT_GET(SPI1_NODE);
static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(LED0_NODE, gpios);
static const struct gpio_dt_spec cs = GPIO_DT_SPEC_GET_OR(DT_NODELABEL(cs_one_pin), gpios, {0});
static struct spi_config spi_cfg = {
.frequency = 1000000U,
.operation = SPI_WORD_SET(8),
.slave = 0
};
static void readRegister(uint8_t reg, uint8_t values[], uint8_t size)
{
int err;
uint8_t tx_buffer[1];
tx_buffer[0] = reg;
struct spi_buf tx_spi_bufs[] = {
{.buf = tx_buffer, .len = sizeof(tx_buffer)}
};
struct spi_buf_set spi_tx_buf_set = {
.buffers = tx_spi_bufs,
.count = 1
};
struct spi_buf rx_spi_bufs[] = {
{.buf = values, .len = size}
};
struct spi_buf_set spi_rx_buf_set = {
.buffers = rx_spi_bufs,
.count = 1
};
gpio_pin_set_dt(&cs, 1U);
do {
err = spi_write(spi1_dev, &spi_cfg, &spi_tx_buf_set);
if(err < 0)
{
break;
}
err = spi_read(spi1_dev, &spi_cfg, &spi_rx_buf_set);
}
while(false);
gpio_pin_set_dt(&cs, 0U);
}
static void readChipID(void) {
uint8_t rx_buf_chipid[1];
readRegister(0x00, rx_buf_chipid, 1);
}
int main(void)
{
int ret;
bool led_state = true;
if (!gpio_is_ready_dt(&led)) {
return 0;
}
if(!device_is_ready(spi1_dev)) {
return 0;
}
ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
if (ret < 0) {
return 0;
}
ret = gpio_pin_configure_dt(&cs, GPIO_OUTPUT);
if (ret < 0) {
return 0;
}
while (1) {
ret = gpio_pin_toggle_dt(&led);
if (ret < 0) {
return 0;
}
readChipID();
printf("LED state: %s\n", led_state ? "ON" : "OFF");
k_msleep(SLEEP_TIME_MS);
}
return 0;
}
Any idea of what I am doing wrong?
I apologize for all these information, but I hope it will help others having the same issues.
Thank you
