Revision 6:cc295531021e, committed 2017-03-30

Comitter:

wbeaumont

Date:

Thu Mar 30 21:54:21 2017 +0000

Parent:

5:c783703a9e28

Commit message:

corrected negative temperature calculation

Changed in this revision

--- a/AT30TSE75x.cpp	Thu Mar 30 18:19:22 2017 +0000
+++ b/AT30TSE75x.cpp	Thu Mar 30 21:54:21 2017 +0000
@@ -11,7 +11,7 @@
 */
 
 
-#define VERSION_AT30TSE75x_SRC  "0.91"  
+#define VERSION_AT30TSE75x_SRC  "0.95"  
 
 #define RegisterLocDownEnable 0 // set this to one to enable permanent NV register locking , never tested with 1 
 
@@ -82,14 +82,14 @@
 uint16_t  AT30TSE75x::set_temperature(float temperature ) {
     uint16_t td;
     uint16_t  sign= 0x8000;
-    if ( temperature  < 0)   temperature = -temperature;
-    else sign=0;
+    if ( temperature  < 0)  { temperature *= -1; }
+    else { sign=0; }
     // this function is only used to calculate limits so we don't care
     // about resolution settings, all is 12 bits
     temperature=temperature *16;
     td=(int)temperature;
+    if (sign){ td = ~td; td=td+1;}
     td= td<<4;
-    if (sign){ td = ~td; td=td+1;}
     td=td|sign;
     return td;    
         
@@ -99,12 +99,13 @@
 float  AT30TSE75x::convert_temperature( uint16_t datain) {
     uint16_t data=datain;
     float temperature;    
-    int8_t sign = 1;
+    float sign = 1;
  
     /* Check if negative and clear sign bit. */
     if (data & (1 << 15)) {
         sign *= -1;
-        data &= ~(1 << 15);
+        data = ~data;
+        data +=1;
     }
  
     /* Convert to temperature. */
@@ -155,7 +156,7 @@
 }     
 
 
-void AT30TSE75x::set_TlowLimitRegister(int &error ,  float temperture, int Nonvolatile) {
+void AT30TSE75x::set_TLowLimitRegister(int &error ,  float temperture, int Nonvolatile) {
     uint8_t reg = TLowReg ;
     if ( Nonvolatile) reg = TLowRegNV;
     set_LimitRegister(error ,reg ,  temperture,  Nonvolatile);
@@ -172,9 +173,9 @@
     if(  CregNV.RegisterLock) { error=44; return; }
     buffer[0]= reg;
     uint16_t td=set_temperature(temperature);
-    uint16_t td_low= td & 0x0F;
+    uint16_t td_low= td & 0xFF;
     buffer[2] = (uint8_t) td_low;
-    td = td >> 8; td= td & 0x0F;
+    td = td >> 8; td= td & 0xFF;
     buffer[1] = (uint8_t) td;
     locerr=_i2c->write(Taddr,(char *)buffer,3,false);
     buffer[0]=  TReg;

--- a/AT30TSE75x.h	Thu Mar 30 18:19:22 2017 +0000
+++ b/AT30TSE75x.h	Thu Mar 30 21:54:21 2017 +0000
@@ -9,7 +9,7 @@
 #include "I2CInterface.h" 
 
 
-#define VERSION_AT30TSE75x_HDR "0.90"
+#define VERSION_AT30TSE75x_HDR "0.95"
 
 /** AT30TSE75x class.
  *  Used for interfacing with a AT30TSE75x temperature sensor and ee-prom  
@@ -23,7 +23,9 @@
  *                  read /write ee-prom 
  *  version 0.86 : added ee-prom write protect mode tested  ( un-protect not tested)
  *  version 0.90 : added all set and get functions for reading the config register(s)
- *                  most of the functions are not tested .                
+ *                  most of the functions are not tested . 
+ *  version 0.95 : found error in set temperature limit registers , corrected set and get limit register 
+ *                  function calls               
  *  this code is only tested with the AT30TSE752  version ( 2 KBit version) 
  *  v 
  *  processor board  for the testing : FRDM-KL25Z 
@@ -131,7 +133,7 @@
     //                          if Nonvolatile=1 and the permanentlock bit is set error will be 43 
     //@param temperature   the temperature to be set in the register 
     //@param Nonvolatile   set the Nonvolataile register if set to none zero 
-    void set_TlowLimitRegister(int &error ,  float temperture, int Nonvolatile=0) ;
+    void set_TLowLimitRegister(int &error ,  float temperture, int Nonvolatile=0) ;
     void set_THighLimitRegister(int &error ,  float temperture, int Nonvolatile=0) ;
     float get_THighLimitRegister(int &error ,   int Nonvolatile=0) ;
     float get_TLowLimitRegister(int &error ,  int Nonvolatile=0) ;