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Update some of the SPI examples to use PICO_DEFAULT_SPI and binary_info

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This commit is contained in:
Andrew Scheller
2021-03-04 11:53:48 +00:00
committed by Graham Sanderson
parent a5363d18a6
commit 83f0eed8c5
5 changed files with 92 additions and 65 deletions
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44
spi/bme280_spi/bme280_spi.c
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@@ -7,6 +7,7 @@
#include <stdio.h>
#include <string.h>
#include "pico/stdlib.h"
#include "pico/binary_info.h"
#include "hardware/spi.h"
/* Example code to talk to a bme280 humidity/temperature/pressure sensor.
@@ -36,12 +37,6 @@
https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bme280-ds002.pdf
*/
#define PIN_MISO 16
#define PIN_CS 17
#define PIN_SCK 18
#define PIN_MOSI 19
#define SPI_PORT spi0
#define READ_BIT 0x80
int32_t t_fine;
@@ -110,24 +105,27 @@ uint32_t compensate_humidity(int32_t adc_H) {
return (uint32_t) (v_x1_u32r >> 12);
}
#ifdef PICO_DEFAULT_SPI_CSN_PIN
static inline void cs_select() {
asm volatile("nop \n nop \n nop");
gpio_put(PIN_CS, 0); // Active low
gpio_put(PICO_DEFAULT_SPI_CSN_PIN, 0); // Active low
asm volatile("nop \n nop \n nop");
}
static inline void cs_deselect() {
asm volatile("nop \n nop \n nop");
gpio_put(PIN_CS, 1);
gpio_put(PICO_DEFAULT_SPI_CSN_PIN, 1);
asm volatile("nop \n nop \n nop");
}
#endif
#if defined(spi_default) && defined(PICO_DEFAULT_SPI_CSN_PIN)
static void write_register(uint8_t reg, uint8_t data) {
uint8_t buf[2];
buf[0] = reg & 0x7f; // remove read bit as this is a write
buf[1] = data;
cs_select();
spi_write_blocking(SPI_PORT, buf, 2);
spi_write_blocking(spi_default, buf, 2);
cs_deselect();
sleep_ms(10);
}
@@ -138,9 +136,9 @@ static void read_registers(uint8_t reg, uint8_t *buf, uint16_t len) {
// so we don't need to keep sending the register we want, just the first.
reg |= READ_BIT;
cs_select();
spi_write_blocking(SPI_PORT, &reg, 1);
spi_write_blocking(spi_default, &reg, 1);
sleep_ms(10);
spi_read_blocking(SPI_PORT, 0, buf, len);
spi_read_blocking(spi_default, 0, buf, len);
cs_deselect();
sleep_ms(10);
}
@@ -184,22 +182,31 @@ static void bme280_read_raw(int32_t *humidity, int32_t *pressure, int32_t *tempe
*temperature = ((uint32_t) buffer[3] << 12) | ((uint32_t) buffer[4] << 4) | (buffer[5] >> 4);
*humidity = (uint32_t) buffer[6] << 8 | buffer[7];
}
#endif
int main() {
stdio_init_all();
#if !defined(spi_default) || !defined(PICO_DEFAULT_SPI_SCK_PIN) || !defined(PICO_DEFAULT_SPI_TX_PIN) || !defined(PICO_DEFAULT_SPI_RX_PIN) || !defined(PICO_DEFAULT_SPI_CSN_PIN)
#warning spi/bme280_spi example requires a board with SPI pins
puts("Default SPI pins were not defined");
#else
printf("Hello, bme280! Reading raw data from registers via SPI...\n");
// This example will use SPI0 at 0.5MHz.
spi_init(SPI_PORT, 500 * 1000);
gpio_set_function(PIN_MISO, GPIO_FUNC_SPI);
gpio_set_function(PIN_SCK, GPIO_FUNC_SPI);
gpio_set_function(PIN_MOSI, GPIO_FUNC_SPI);
spi_init(spi_default, 500 * 1000);
gpio_set_function(PICO_DEFAULT_SPI_RX_PIN, GPIO_FUNC_SPI);
gpio_set_function(PICO_DEFAULT_SPI_SCK_PIN, GPIO_FUNC_SPI);
gpio_set_function(PICO_DEFAULT_SPI_TX_PIN, GPIO_FUNC_SPI);
// Make the SPI pins available to picotool
bi_decl(bi_3pins_with_func(PICO_DEFAULT_SPI_RX_PIN, PICO_DEFAULT_SPI_TX_PIN, PICO_DEFAULT_SPI_SCK_PIN, GPIO_FUNC_SPI));
// Chip select is active-low, so we'll initialise it to a driven-high state
gpio_init(PIN_CS);
gpio_set_dir(PIN_CS, GPIO_OUT);
gpio_put(PIN_CS, 1);
gpio_init(PICO_DEFAULT_SPI_CSN_PIN);
gpio_set_dir(PICO_DEFAULT_SPI_CSN_PIN, GPIO_OUT);
gpio_put(PICO_DEFAULT_SPI_CSN_PIN, 1);
// Make the CS pin available to picotool
bi_decl(bi_1pin_with_name(PICO_DEFAULT_SPI_CSN_PIN, "CS"));
// See if SPI is working - interrograte the device for its I2C ID number, should be 0x60
uint8_t id;
@@ -230,4 +237,5 @@ int main() {
}
return 0;
#endif
}