DS1820 - Dallas' DS1820 family temperature sensor. For mor…

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Dallas' DS1820 family temperature sensor. For more details see [https://developer.mbed.org/users/hudakz/code/DS1820/wiki/Homepage]

Dependencies: OneWire

Dependents: BLE_nRF24L01 frdm_serialfgmp gather_sensor_data UltiSaverController ... more

Some programs using the DS1820 library:

Import program DS1820_Hello

Simple DS1820 sensor demo showing how to use the DS1820 library [https://developer.mbed.org/users/hudakz/code/DS1820/]

Import program BLE_nRF24L01

Bluetooth Low Energy (BLE) beacon with nRF24L01(+). Data is received and displayed by Android device (Android app source code is attached).

Examples of use:

Single DS1820 sensor

/*
 * Single DS1820 sensor GPIO driven
 *
 * Note: Don't forget to connect a 4.7k Ohm resistor 
 *       between the DS1820's data pin and the +3.3V pin
 *
 *           ----------------
 *          |                |   ----------------------->  +3.3V
 *          |   MBED BOARD   |  |
 *          |                |  |   ------
 *          |          +3.3V |--o--| 4.7k |-------
 *          |                |      ------        |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |           GPIO |--------------------o----->  1-wire bus/line
 *          |                |
 *          |                |
 *          |            GND |-------------------------->  GND
 *          |                |
 *           ----------------
 *
 */
 
#include "mbed.h"
#include "DS1820.h"
 
Serial serial(USBTX, USBRX);
 
int main() {
    DS1820  ds1820(D8);    // substitute D8 with actual mbed pin name connected to the DS1820 data pin    
                             
    if(ds1820.begin()) {
        while(1) {
            ds1820.startConversion();     // start temperature conversion
            ThisThread::sleep_for(1000);  // let DS1820 complete the temperature conversion
            serial.printf("temp = %3.1f\r\n", ds1820.read());     // read temperature
        }
    } else
        serial.printf("No DS1820 sensor found!\r\n");
}

Single DS1820 sensor. Data integrity is assured by performing CRC.

/*
 * Single DS1820 sensor GPIO driven + performing CRC
 *
 * Note: Don't forget to connect a 4.7k Ohm resistor 
 *       between the DS1820's data pin and the +3.3V pin
 *
 *           ----------------
 *          |                |   ----------------------->  +3.3V
 *          |   MBED BOARD   |  |
 *          |                |  |   ------
 *          |          +3.3V |--o--| 4.7k |-------
 *          |                |      ------        |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |           GPIO |--------------------o----->  1-wire bus/line
 *          |                |
 *          |                |
 *          |            GND |-------------------------->  GND
 *          |                |
 *           ----------------
 *
 */
 
#include "mbed.h"
#include "DS1820.h"
 
Serial serial(USBTX, USBRX);
 
int main() {
    DS1820  ds1820(D8);    // substitute D8 with actual mbed pin name connected to the DS1820 data pin   
    float   temp = 0;
    int     error = 0; 
                             
    if(ds1820.begin()) {
        while(1) {
            ds1820.startConversion();    // start temperature conversion
            ThisThread::sleep_for(1000); // let DS1820 complete the temperature conversion
            error = ds1820.read(temp);   // read temperature from DS1820 and perform cyclic redundancy check (CRC)
            switch(error) {
            case 0:    // no errors -> 'temp' contains the value of measured temperature
                serial.printf("temp = %3.1f\r\n", temp);
                break;
            case 1:    // no sensor present -> 'temp' is not updated
                serial.printf("no sensor present\n\r");
                break;
            case 2:    // CRC error -> 'temp' is not updated
                serial.printf("CRC error\r\n");
            } 
        }
    } else
        serial.printf("No DS1820 sensor found!\r\n");
}

Several DS1820 sensors connected to the same 1-wire bus.

/*
 * Multiple sensors GPIO driven
 *
 * Note: Don't forget to connect a 4.7k Ohm resistor 
 *       between the 1-wire bus data line and the +3.3V rail
 *
 *           ----------------
 *          |                |   ----------------------->  +3.3V
 *          |   MBED BOARD   |  |
 *          |                |  |   ------
 *          |          +3.3V |--o--| 4.7k |-------
 *          |                |      ------        |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |                |                    |
 *          |           GPIO |--------------------o----->  1-wire bus/line
 *          |                |
 *          |                |
 *          |            GND |-------------------------->  GND
 *          |                |
 *           ----------------
 *
 */

#include "mbed.h"
#include "DS1820.h"

#define     MAX_SENSOSRS   32   // max number of DS1820 sensors to be connected to the 1-wire bus (max 256)

DS1820*     ds1820[MAX_SENSOSRS];
Serial      pc(USBTX, USBRX);
DigitalOut  led(LED1);
OneWire     oneWire(D8);        // substitute D8 with the actual pin name connected to the 1-wire bus
int         sensorsFound = 0;   // counts the actually found DS1820 sensors

int main()
{
    pc.printf("\r\n--Starting--\r\n");
    
    //Enumerate (i.e. detect) DS1820 sensors on the 1-wire bus
    for (sensorsFound = 0; sensorsFound < MAX_SENSOSRS; sensorsFound++) {
        ds1820[sensorsFound] = new DS1820(&oneWire);
        if (!ds1820[sensorsFound]->begin()) {
            delete ds1820[sensorsFound];
            break;
        }
    }

    switch (sensorsFound) {
        case 0:
            pc.printf("No DS1820 sensor found!\r\n");
            return -1;

        case 1:
            pc.printf("One DS1820 sensor found.\r\n");
            break;

        default:
            pc.printf("Found %d DS1820 sensors.\r\n", sensorsFound);
    }

    while (1) {
        pc.printf("----------------\r\n");
        for (int i = 0; i < sensorsFound; i++)
            ds1820[i]->startConversion();        // start temperature conversion from analog to digital
        ThisThread::sleep_for(1000);             // let DS1820 sensors complete the temperature conversion
        for (int i = 0; i < sensorsFound; i++) {
            if (ds1820[i]->isPresent())
                pc.printf("temp[%d] = %3.1f%cC\r\n", i, ds1820[i]->read(), 176); // read temperature
        }
    }
}

Several DS1820 sensors connected to the same 1-wire bus. UART is used to implement the bus

/*
 * Multiple sensors UART driven:
 * 
 *          UART is driving the 1-Wire Bus Master according to Maxim Integrated application note
 *
 *          https://www.maximintegrated.com/en/design/technical-documents/tutorials/2/214.html
 *
 *          In addition to the 4.7k Ohm resistor between the 1-wire data bus/line and the +3.3V pin,
 *          a 470 Ohm resistor shall be tied to the UART's tx and rx pin. UART's rx pin is then used
 *          as 1-wire data bus/line.
 *
 *           ----------------
 *          |                |   ----------------------->  +3.3V
 *          |   MBED BOARD   |  |
 *          |                |  |   ------
 *          |          +3.3V |--o--| 4.7k |-------
 *          |                |      ------        |
 *          |                |      ------        |
 *          |        UART TX |-----|  470 |---    |
 *          |                |      ------    |   |
 *          |                |                |   |
 *          |        UART RX |----------------o---o----->  1-wire bus/line
 *          |                |
 *          |                |
 *          |            GND |-------------------------->  GND
 *          |                |
 *           ----------------
 *
 */
#include "mbed.h"
#include "DS1820.h"

#define MAX_SENSOSRS    32      // max number of DS1820 sensors to be connected to the 1-wire bus (max 256)
DS1820*     ds1820[MAX_SENSOSRS];
DigitalOut  led(LED1);
OneWire     oneWire(p9, p10);       // LPC1768 (UART Tx pin, UART Rx pin)
//OneWire     oneWire(PA_0, PA_1);    // NUCLE0-F446RE (UART Tx pin, UART Rx pin)
int         sensorsFound = 0;       // counts the actually found DS1820 sensors

/**
 * @brief
 * @note
 * @param
 * @retval
 */
int main()
{
    printf("\r\n--Starting--\r\n");

    //Enumerate (i.e. detect) DS1820 sensors on the 1-wire bus
    for (sensorsFound = 0; sensorsFound < MAX_SENSOSRS; sensorsFound++) {
        ds1820[sensorsFound] = new DS1820(&oneWire);
        if (!ds1820[sensorsFound]->begin()) {
            delete ds1820[sensorsFound];
            break;
        }
    }

    switch (sensorsFound) {
        case 0:
            printf("No DS1820 sensor found!\r\n");
            return -1;

        case 1:
            printf("One DS1820 sensor found.\r\n");
            break;

        default:
            printf("Found %d DS1820 sensors.\r\n", sensorsFound);
    }

    while (1) {
        led = !led;

        printf("----------------\r\n");
        for (int i = 0; i < sensorsFound; i++)
            ds1820[i]->startConversion();   // start temperature conversion from analog to digital
        #if (MBED_MAJOR_VERSION > 5)
            ThisThread::sleep_for(1s);
        #else
            wait(1);
        #endif


        for (int i = 0; i < sensorsFound; i++) {
            if (ds1820[i]->isPresent())
                printf("temp[%d] = %3.1f%cC\r\n", i, ds1820[i]->read(), 176);   // read temperature
        }
    }
}

DS1820.h@20:98c261bcb399, 2019-03-10 (annotated)

Committer:: hudakz
Date:: Sun Mar 10 13:19:03 2019 +0000
Revision:: 20:98c261bcb399
Parent:: 14:b02fa18b294a
Child:: 23:74a4ff420541

Added multidrop capability.

Who changed what in which revision?

User	Revision	Line number	New contents of line
hudakz	0:433af64321d5	1	#ifndef DS1820_H_
hudakz	0:433af64321d5	2	#define DS1820_H_
hudakz	0:433af64321d5	3
hudakz	0:433af64321d5	4	#include <OneWire.h>
hudakz	0:433af64321d5	5
hudakz	14:b02fa18b294a	6	/**
hudakz	14:b02fa18b294a	7	* Dallas' DS1820 family temperature sensor.
hudakz	14:b02fa18b294a	8	* This library depends on the OneWire library (Dallas' 1-Wire bus protocol implementation)
hudakz	14:b02fa18b294a	9	* available at <http://developer.mbed.org/users/hudakz/code/OneWire/>
hudakz	14:b02fa18b294a	10	*
hudakz	14:b02fa18b294a	11	* Example of use:
hudakz	14:b02fa18b294a	12	*
hudakz	14:b02fa18b294a	13	* @code
hudakz	20:98c261bcb399	14	*
hudakz	20:98c261bcb399	15	* Single sensor.
hudakz	14:b02fa18b294a	16	*
hudakz	20:98c261bcb399	17	* #include "mbed.h"
hudakz	20:98c261bcb399	18	* #include "DS1820.h"
hudakz	20:98c261bcb399	19	*
hudakz	20:98c261bcb399	20	* Serial pc(USBTX, USBRX);
hudakz	20:98c261bcb399	21	* DigitalOut led(LED1);
hudakz	20:98c261bcb399	22	* DS1820 ds1820(D8); // substitute D8 with actual mbed pin name connected to 1-wire bus
hudakz	20:98c261bcb399	23	* float temp = 0;
hudakz	20:98c261bcb399	24	* int result = 0;
hudakz	20:98c261bcb399	25	*
hudakz	20:98c261bcb399	26	* int main()
hudakz	20:98c261bcb399	27	* {
hudakz	20:98c261bcb399	28	* pc.printf("\r\n--Starting--\r\n");
hudakz	20:98c261bcb399	29	* if (ds1820.begin()) {
hudakz	20:98c261bcb399	30	* while (1) {
hudakz	20:98c261bcb399	31	* ds1820.startConversion(); // start temperature conversion from analog to digital
hudakz	20:98c261bcb399	32	* wait(1.0); // let DS1820 complete the temperature conversion
hudakz	20:98c261bcb399	33	* result = ds1820.read(temp); // read temperature from DS1820 and perform cyclic redundancy check (CRC)
hudakz	20:98c261bcb399	34	* switch (result) {
hudakz	20:98c261bcb399	35	* case 0: // no errors -> 'temp' contains the value of measured temperature
hudakz	20:98c261bcb399	36	* pc.printf("temp = %3.1f%cC\r\n", temp, 176);
hudakz	20:98c261bcb399	37	* break;
hudakz	20:98c261bcb399	38	*
hudakz	20:98c261bcb399	39	* case 1: // no sensor present -> 'temp' is not updated
hudakz	20:98c261bcb399	40	* pc.printf("no sensor present\n\r");
hudakz	20:98c261bcb399	41	* break;
hudakz	20:98c261bcb399	42	*
hudakz	20:98c261bcb399	43	* case 2: // CRC error -> 'temp' is not updated
hudakz	20:98c261bcb399	44	* pc.printf("CRC error\r\n");
hudakz	20:98c261bcb399	45	* }
hudakz	20:98c261bcb399	46	*
hudakz	20:98c261bcb399	47	* led = !led;
hudakz	20:98c261bcb399	48	* }
hudakz	20:98c261bcb399	49	* }
hudakz	20:98c261bcb399	50	* else
hudakz	20:98c261bcb399	51	* pc.printf("No DS1820 sensor found!\r\n");
hudakz	20:98c261bcb399	52	* }
hudakz	20:98c261bcb399	53	*
hudakz	20:98c261bcb399	54	*
hudakz	20:98c261bcb399	55	* More sensors connected to the same 1-wire bus.
hudakz	20:98c261bcb399	56	*
hudakz	20:98c261bcb399	57	* #include "mbed.h"
hudakz	20:98c261bcb399	58	* #include "DS1820.h"
hudakz	20:98c261bcb399	59	*
hudakz	20:98c261bcb399	60	* #define SENSORS_COUNT 64 // number of DS1820 sensors to be connected to the 1-wire bus (max 256)
hudakz	20:98c261bcb399	61	*
hudakz	20:98c261bcb399	62	* Serial pc(USBTX, USBRX);
hudakz	20:98c261bcb399	63	* DigitalOut led(LED1);
hudakz	20:98c261bcb399	64	* OneWire oneWire(D8); // substitute D8 with actual mbed pin name connected to the DS1820 data pin
hudakz	20:98c261bcb399	65	* DS1820* ds1820[SENSORS_COUNT];
hudakz	20:98c261bcb399	66	* int sensors_found = 0; // counts the actually found DS1820 sensors
hudakz	20:98c261bcb399	67	* float temp = 0;
hudakz	20:98c261bcb399	68	* int result = 0;
hudakz	14:b02fa18b294a	69	*
hudakz	14:b02fa18b294a	70	* int main() {
hudakz	20:98c261bcb399	71	* int i = 0;
hudakz	20:98c261bcb399	72	*
hudakz	20:98c261bcb399	73	* pc.printf("\r\n Starting \r\n");
hudakz	20:98c261bcb399	74	* //Enumerate (i.e. detect) DS1820 sensors on the 1-wire bus
hudakz	20:98c261bcb399	75	* for(i = 0; i < SENSORS_COUNT; i++) {
hudakz	20:98c261bcb399	76	* ds1820[i] = new DS1820(&oneWire);
hudakz	20:98c261bcb399	77	* if(!ds1820[i]->begin()) {
hudakz	20:98c261bcb399	78	* delete ds1820[i];
hudakz	20:98c261bcb399	79	* break;
hudakz	20:98c261bcb399	80	* }
hudakz	20:98c261bcb399	81	* }
hudakz	20:98c261bcb399	82	*
hudakz	20:98c261bcb399	83	* sensors_found = i;
hudakz	20:98c261bcb399	84	*
hudakz	20:98c261bcb399	85	* if (sensors_found == 0) {
hudakz	20:98c261bcb399	86	* pc.printf("No DS1820 sensor found!\r\n");
hudakz	20:98c261bcb399	87	* return -1;
hudakz	20:98c261bcb399	88	* }
hudakz	20:98c261bcb399	89	* else
hudakz	20:98c261bcb399	90	* pc.printf("Found %d sensors.\r\n", sensors_found);
hudakz	20:98c261bcb399	91	*
hudakz	20:98c261bcb399	92	* while(1) {
hudakz	20:98c261bcb399	93	* pc.printf("-------------------\r\n");
hudakz	20:98c261bcb399	94	* for(i = 0; i < sensors_found; i++)
hudakz	20:98c261bcb399	95	* ds1820[i]->startConversion(); // start temperature conversion from analog to digital
hudakz	20:98c261bcb399	96	* wait(1.0); // let DS1820s complete the temperature conversion
hudakz	20:98c261bcb399	97	* for(int i = 0; i < sensors_found; i++) {
hudakz	20:98c261bcb399	98	* if(ds1820[i]->isPresent())
hudakz	20:98c261bcb399	99	* pc.printf("temp[%d] = %3.1f%cC\r\n", i, ds1820[i]->read(), 176); // read temperature
hudakz	20:98c261bcb399	100	* }
hudakz	20:98c261bcb399	101	* }
hudakz	14:b02fa18b294a	102	* }
hudakz	20:98c261bcb399	103	*
hudakz	14:b02fa18b294a	104	* @endcode
hudakz	14:b02fa18b294a	105	*
hudakz	14:b02fa18b294a	106	* Note: Don't forget to connect a 4.7k Ohm resistor
hudakz	14:b02fa18b294a	107	* between the DS1820's data pin and the +3.3V pin
hudakz	14:b02fa18b294a	108	*
hudakz	14:b02fa18b294a	109	*/
hudakz	0:433af64321d5	110	class DS1820
hudakz	0:433af64321d5	111	{
hudakz	20:98c261bcb399	112	OneWire *oneWire;
hudakz	8:8dfdd1603e4d	113	bool present;
hudakz	8:8dfdd1603e4d	114	bool model_s;
hudakz	0:433af64321d5	115	uint8_t data[12];
hudakz	0:433af64321d5	116	uint8_t addr[8];
hudakz	0:433af64321d5	117	float toFloat(uint16_t word);
hudakz	20:98c261bcb399	118	static uint8_t lastAddr[8];
hudakz	20:98c261bcb399	119
hudakz	0:433af64321d5	120	public:
hudakz	0:433af64321d5	121	DS1820(PinName pin);
hudakz	20:98c261bcb399	122	// DS1820(char model, PinName pin);
hudakz	20:98c261bcb399	123	DS1820(OneWire* wire);
hudakz	0:433af64321d5	124	bool begin(void);
hudakz	8:8dfdd1603e4d	125	bool isPresent();
hudakz	4:adf4e7972d73	126	void setResolution(uint8_t res);
hudakz	0:433af64321d5	127	void startConversion(void);
hudakz	0:433af64321d5	128	float read(void);
hudakz	13:b593a82ce790	129	uint8_t read(float& temp);
hudakz	0:433af64321d5	130	};
hudakz	0:433af64321d5	131	#endif /* DS1820_H_ */

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Type:	Library
Created:	15 Mar 2015
Imports:	1239
Forks:	7
Commits:	25
Dependents:	34
Dependencies:	1
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