Diff: ntc.h

Revision:

3:1eb4f5296281

Parent:

2:c843c06cc651

Child:

4:5d0dfa665cba

--- a/ntc.h	Fri Apr 07 16:36:47 2017 +0000
+++ b/ntc.h	Sat Apr 08 01:17:20 2017 +0000
@@ -1,7 +1,10 @@
 /*
  * mbed library for NTC analog pin that translates an A:D input
- *     voltage to a temperature value
+ *     voltage to a temperature value.
+ *
+ *
  *     topology:  Vref -> SeriesRes -> A:D -> NTC -> GND
+ *
 */
 
 #ifndef        MBED_NTC
@@ -54,11 +57,41 @@
      *  #include "mbed.h"
      *  #include "ntc.h" 
      *
+     *  #define NTC_VREF        3.3f
+     *  #define NTC_AD_RESOL    65536.0f
+     *
+     *  // Connections:
+     *
+     *  //      3.3V (or other Vref)
+     *  //     --+--
+     *  //       |
+     *  //      -+-
+     *  //     |   |
+     *  //     |   |
+     *  //     |   | Series
+     *  //     |   | Resistor
+     *  //     |   |
+     *  //      -+-
+     *  //       |
+     *  //       +---> To A:D
+     *  //       |
+     *  //      -+-
+     *  //     |   |
+     *  //     |   |
+     *  //     |   | NTC
+     *  //     |   | 
+     *  //     |   |
+     *  //      -+-
+     *  //       |
+     *  //     --+--
+     *  //      ---  Ground
+     *  //       -
+     *
      *  
      *  const NTC_TypeDef ntc_my_paramtr = {
      *    // Vref
-     *    3.3f,               // Vref
-     *    65535.0f,           // A:D 16-bit resolution
+     *    NTC_VREF,           // Vref
+     *    NTC_AD_RES          // A:D 16-bit resolution
      *    // muRata NCP15XH103J03RC
      *    10000,              // NTC resistance
      *    5,                  // NTC initial tolerance
@@ -78,9 +111,11 @@
      *  main() {
      *      printf("\r\n\r\n-------------------------------------------\r\n");
      *      printf("NTC Res: %5d   B25/50: %4d   B25/80: %4d   B25/85: %4d   B25/100: %4d   SeriesR: %d\r\n", 
-     *              ntc.get_ntc_res(), ntc.get_ntc_beta_2550(), ntc.get_ntc_beta_2580(), ntc.get_ntc_beta_2585(), ntc.get_ntc_beta_25100(),  ntc.get_series_res());
+     *              ntc.get_ntc_res(), ntc.get_ntc_beta_2550(), ntc.get_ntc_beta_2580(), ntc.get_ntc_beta_2585(), ntc.get_ntc_beta_25100(),  
+     *              ntc.get_series_res());
      *      uint16_t ad = ntc.read_ad_reg();
-     *      printf("NTC A:D Val: %5d   Volt A:D: %.6f   NTC-R_now: %7.1f    Temp: %+.2f\r\n", ad, 3.3f / 65536.0f * (float)ad, ntc.get_ntc_res_viaAD(ad), ntc.get_ntc_temp(NTC::B25_85, ad));
+     *      printf("NTC A:D Val: %5d   Volt A:D: %.6f   NTC-R_now: %7.1f    Temp: %+.2f\r\n", ad, 
+     *              NTC_VREF / NTC_AD_RESOL * (float)ad, ntc.get_ntc_res_viaAD(ad), ntc.get_ntc_temp(NTC::B25_85, ad));
      *
      *      while(1) {
      *          printf("Temp: %+.2f\r\n", ntc.get_ntc_temp(NTC::B25_85));
@@ -162,17 +197,17 @@
     /** calculate NTC resistance based on A:D reading
       * @param none
       * @param din optional read from read_ad_reg().
-      * @param din if missing or 0, read_ad_reg() is executed first.
-      * @param din if != 0, then local value of din is used.
+      * @param din -> if missing or 0, read_ad_reg() value is used for calculation
+      * @param din -> if != 0, then value of din is used for calculation
       * @return resistance of NTC
       */
     float get_ntc_res_viaAD(uint16_t din = NULL);
       
     /** calculate NTC temperaure
       * @param curve Beta curve to use. See ntcBetaCurve {};
-      * @param din optional read from read_ad_reg().
-      * @param din if missing or 0, read_ad_reg() is executed first.
-      * @param din if != 0, then local value of din is used.
+      * @param din optional read from read_ad_reg()
+      * @param din -> if missing or 0, read_ad_reg() value is used for calculation
+      * @param din -> if != 0, then value of din is used for calculation
       * @return temperature of NTC
       */
     float get_ntc_temp(int curve, uint16_t din = NULL);