Diff: DS1820.h

Revision:

20:98c261bcb399

Parent:

14:b02fa18b294a

Child:

23:74a4ff420541

--- a/DS1820.h	Sun Jan 27 18:02:01 2019 +0000
+++ b/DS1820.h	Sun Mar 10 13:19:03 2019 +0000
@@ -11,25 +11,96 @@
  * Example of use:
  * 
  * @code
- * #include "DS1820.h"
+ * 
+ * Single sensor.
  *
- * Serial serial(USBTX, USBRX);
+ * #include "mbed.h"
+ * #include "DS1820.h"
+ * 
+ * Serial      pc(USBTX, USBRX);
+ * DigitalOut  led(LED1);
+ * DS1820      ds1820(D8);  // substitute D8 with actual mbed pin name connected to 1-wire bus
+ * float       temp = 0;
+ * int         result = 0;
+ * 
+ * int main()
+ * {
+ *     pc.printf("\r\n--Starting--\r\n");
+ *     if (ds1820.begin()) {
+ *         while (1) {
+ *             ds1820.startConversion();   // start temperature conversion from analog to digital
+ *             wait(1.0);                  // let DS1820 complete the temperature conversion
+ *             result = ds1820.read(temp); // read temperature from DS1820 and perform cyclic redundancy check (CRC)
+ *             switch (result) {
+ *                 case 0:                 // no errors -> 'temp' contains the value of measured temperature
+ *                     pc.printf("temp = %3.1f%cC\r\n", temp, 176);
+ *                     break;
+ * 
+ *                 case 1:                 // no sensor present -> 'temp' is not updated
+ *                     pc.printf("no sensor present\n\r");
+ *                     break;
+ * 
+ *                 case 2:                 // CRC error -> 'temp' is not updated
+ *                     pc.printf("CRC error\r\n");
+ *             }
+ * 
+ *             led = !led;
+ *         }
+ *     }
+ *     else
+ *         pc.printf("No DS1820 sensor found!\r\n");
+ * }
+ * 
+ * 
+ * More sensors connected to the same 1-wire bus.
+ * 
+ * #include "mbed.h"
+ * #include "DS1820.h"
+ * 
+ * #define     SENSORS_COUNT   64      // number of DS1820 sensors to be connected to the 1-wire bus (max 256)
+ * 
+ * Serial      pc(USBTX, USBRX);
+ * DigitalOut  led(LED1);
+ * OneWire     oneWire(D8);            // substitute D8 with actual mbed pin name connected to the DS1820 data pin
+ * DS1820*     ds1820[SENSORS_COUNT];
+ * int         sensors_found = 0;      // counts the actually found DS1820 sensors
+ * float       temp = 0;
+ * int         result = 0;
  * 
  * int main() {
- *     DS1820  ds1820(PA_9);    // substitute PA_9 with actual mbed pin name connected to the DS1820 data pin
- *
- *     if(ds1820.begin()) {
- *        ds1820.startConversion();
- *        wait(1.0);
- *        while(1) {
- *            serial.printf("temp = %3.1f\r\n", ds1820.read());     // read temperature
- *            ds1820.startConversion();     // start temperature conversion
- *            wait(1.0);                    // let DS1820 complete the temperature conversion
- *        }
- *    } else
- *        serial.printf("No DS1820 sensor found!\r\n");
+ *     int i = 0;
+ *     
+ *     pc.printf("\r\n Starting \r\n");
+ *     //Enumerate (i.e. detect) DS1820 sensors on the 1-wire bus
+ *     for(i = 0; i < SENSORS_COUNT; i++) {
+ *         ds1820[i] = new DS1820(&oneWire);
+ *         if(!ds1820[i]->begin()) {
+ *             delete ds1820[i];
+ *             break;
+ *         }
+ *     }
+ *     
+ *     sensors_found = i;
+ *     
+ *     if (sensors_found == 0) {
+ *         pc.printf("No DS1820 sensor found!\r\n");
+ *         return -1;
+ *     }
+ *     else
+ *         pc.printf("Found %d sensors.\r\n", sensors_found);
+ *     
+ *     while(1) {
+ *         pc.printf("-------------------\r\n");
+ *         for(i = 0; i < sensors_found; i++)
+ *             ds1820[i]->startConversion();   // start temperature conversion from analog to digital       
+ *         wait(1.0);                          // let DS1820s complete the temperature conversion
+ *         for(int i = 0; i < sensors_found; i++) {
+ *             if(ds1820[i]->isPresent())
+ *                 pc.printf("temp[%d] = %3.1f%cC\r\n", i, ds1820[i]->read(), 176);     // read temperature
+ *         }
+ *     }
  * }
- *
+ * 
  * @endcode
  * 
  * Note: Don't forget to connect a 4.7k Ohm resistor 
@@ -38,16 +109,18 @@
  */
 class   DS1820
 {
-    OneWire oneWire;
+    OneWire *oneWire;
     bool    present;    
     bool    model_s;
     uint8_t data[12];
     uint8_t addr[8];
     float   toFloat(uint16_t word);
+    static  uint8_t lastAddr[8];
+    
 public:
-
     DS1820(PinName pin);
-    DS1820(char model, PinName pin);
+//    DS1820(char model, PinName pin);
+    DS1820(OneWire* wire);
     bool   begin(void);
     bool   isPresent();
     void   setResolution(uint8_t res);