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Implement new ds18b20 APIs

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This commit is contained in:
Alex Stewart 2016-03-17 16:03:46 -07:00
parent 60e468bdb2
commit 494c2d9cec
4 changed files with 311 additions and 46 deletions
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89
examples/ds18b20_onewire/ds18b20_onewire.c
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@ -1,55 +1,78 @@
/* ds18b20 - Retrieves temperature from ds18b20 sensors and print it out.
/* ds18b20_onewire.c - Retrieves readings from one or more DS18B20 temperature
* sensors, and prints the results to stdout.
*
* This sample code is in the public domain.,
*/
#include "espressif/esp_common.h"
#include "esp/uart.h"
#include "FreeRTOS.h"
#include "task.h"
#include "timers.h"
#include "queue.h"
#include "esp/uart.h"
// DS18B20 driver
#include "ds18b20/ds18b20.h"
void print_temperature(void *pvParameters)
{
int delay = 500;
uint8_t amount = 0;
// Declare amount of sensors
uint8_t sensors = 2;
ds_sensor_t t[sensors];
// Use GPIO 13 as one wire pin.
uint8_t GPIO_FOR_ONE_WIRE = 13;
#define SENSOR_GPIO 13
#define MAX_SENSORS 8
#define RESCAN_INTERVAL 8
#define LOOP_DELAY_MS 250
void print_temperature(void *pvParameters) {
ds18b20_addr_t addrs[MAX_SENSORS];
float temps[MAX_SENSORS];
int sensor_count;
// There is no special initialization required before using the ds18b20
// routines. However, we make sure that the internal pull-up resistor is
// enabled on the GPIO pin so that one can connect up a sensor without
// needing an external pull-up (Note: The internal (~47k) pull-ups of the
// ESP8266 do appear to work, at least for simple setups (one or two sensors
// connected with short leads), but do not technically meet the pull-up
// requirements from the DS18B20 datasheet and may not always be reliable.
// For a real application, a proper 4.7k external pull-up resistor is
// recommended instead!)
gpio_set_pullup(SENSOR_GPIO, true, true);
while(1) {
// Search all DS18B20, return its amount and feed 't' structure with result data.
amount = ds18b20_read_all(GPIO_FOR_ONE_WIRE, t);
// Every RESCAN_INTERVAL samples, check to see if the sensors connected
// to our bus have changed.
sensor_count = ds18b20_scan_devices(SENSOR_GPIO, addrs, MAX_SENSORS);
if (amount < sensors){
printf("Something is wrong, I expect to see %d sensors \nbut just %d was detected!\n", sensors, amount);
}
if (sensor_count < 1) {
printf("\nNo sensors detected!\n");
} else {
printf("\n%d sensors detected:\n", sensor_count);
// If there were more sensors found than we have space to handle,
// just report the first MAX_SENSORS..
if (sensor_count > MAX_SENSORS) sensor_count = MAX_SENSORS;
for (int i = 0; i < amount; ++i)
{
int intpart = (int)t[i].value;
int fraction = (int)((t[i].value - intpart) * 100);
// Multiple "" here is just to satisfy compiler and don`t raise 'hex escape sequence out of range' warning.
printf("Sensor %d report: %d.%02d ""\xC2""\xB0""C\n",t[i].id, intpart, fraction);
// Do a number of temperature samples, and print the results.
for (int i = 0; i < RESCAN_INTERVAL; i++) {
ds18b20_measure_and_read_multi(SENSOR_GPIO, addrs, sensor_count, temps);
for (int j = 0; j < sensor_count; j++) {
// The DS18B20 address is a 64-bit integer, but newlib-nano
// printf does not support printing 64-bit values, so we
// split it up into two 32-bit integers and print them
// back-to-back to make it look like one big hex number.
uint32_t addr0 = addrs[j] >> 32;
uint32_t addr1 = addrs[j];
float temp_c = temps[j];
float temp_f = (temp_c * 1.8) + 32;
printf(" Sensor %08x%08x reports %f deg C (%f deg F)\n", addr0, addr1, temp_c, temp_f);
}
printf("\n");
// Wait for a little bit between each sample (note that the
// ds18b20_measure_and_read_multi operation already takes at
// least 750ms to run, so this is on top of that delay).
vTaskDelay(LOOP_DELAY_MS / portTICK_RATE_MS);
}
}
printf("\n");
vTaskDelay(delay / portTICK_RATE_MS);
}
}
void user_init(void)
{
void user_init(void) {
uart_set_baud(0, 115200);
printf("SDK version:%s\n", sdk_system_get_sdk_version());
xTaskCreate(&print_temperature, (signed char *)"print_temperature", 256, NULL, 2, NULL);
}