Revision 6:6b9fc31d51b0, committed 2015-05-20

Comitter:

dipi

Date:

Wed May 20 09:17:24 2015 +0000

Parent:

5:2dc8c3f02788

Commit message:

Beta version

Changed in this revision

--- a/ad5933.cpp	Wed May 13 14:07:40 2015 +0000
+++ b/ad5933.cpp	Wed May 20 09:17:24 2015 +0000
@@ -23,23 +23,22 @@
 #define INCR_FREQ  0x30     // increment frequency
 #define REPE_FREQ  0x40     // repeat frequency
 #define STANDBY    0xB0     // standby
+#define POWERDOWN  0xA0     // PowerDown modus
 #define MEAS_TEMP  0x90     // temperature
 
 #define WRITE_CMD  0x1A     // adress + write command
 #define READ_CMD   0x1B     // adress + read command
 
 #define CLOCK_FREQ 0x00F42400
+#define I2C_FREQ   400000
+
+#define WAITTIME   1800     // time to wait before polling for response
 
 AD5933::AD5933(PinName sda, PinName scl, bool extClk) : sCom(sda, scl)
 {
-    sCom.frequency(400000);
-    firstMeasurement = true;
+    sCom.frequency(I2C_FREQ);
     PGAandVoltout = 0x00;
     _extClk = extClk;
-    //if(_extClk)
-    //    setRegister(0x81, 0x08);
-    //else
-    //    setRegister(0x81, 0x00);
 }
 
 bool AD5933::gotoAdressPointer(uint8_t Adress)
@@ -114,13 +113,28 @@
     output &= setRegister(0x88,(nrOfSteps >> 8));
     output &= setRegister(0x89,nrOfSteps);
 
-    firstMeasurement = true;
+    return output;
+}
+
+bool AD5933::initFrequencySweepParam(unsigned int startFreq, unsigned int stepFreq, unsigned int nrOfSteps, unsigned int nrOfCycles, bool PGA, int RangeNr)
+{
+    bool output = setFrequencySweepParam(startFreq, stepFreq, nrOfSteps);
+    output &= setSettlingTime(nrOfCycles);
+    output &= standby();
+    output &= setAnalogCircuit(PGA, RangeNr);
+    output &= setControlReg(INIT_FREQ);
+    wait_ms(5);
+    output &= setControlReg(INIT_SWEEP);
+    wait_us(WAITTIME);
+    output &= getData();
+
     return output;
 }
 
 bool AD5933::setSettlingTime(unsigned int nrOfCycles)
 {
     bool output = true;
+
     if (nrOfCycles > 1022) {
         output &= setRegister(0x8A,((nrOfCycles/4) >> 8) | 0x06);
         output &= setRegister(0x8B,(nrOfCycles/4));
@@ -154,8 +168,15 @@
             PGAandVoltout |= 0x02;
             break;
     }
-    firstMeasurement = true;
-    return true;
+
+    uint8_t data = 0x00;
+    if(_extClk)
+        data |= 0x08;
+
+    bool output = setRegister(0x81, data);
+    output &= setRegister(0x80,PGAandVoltout);
+
+    return output;
 }
 
 bool AD5933::reset()
@@ -170,26 +191,23 @@
 bool AD5933::standby()
 {
     return setControlReg(STANDBY);
+}
 
+bool AD5933::powerdown()
+{
+    return setControlReg(POWERDOWN);
 }
 
 bool AD5933::Measure(bool increment)
 {
-    if(firstMeasurement) {
-        setControlReg(INIT_FREQ);
-        wait_ms(1000);
-
-        setControlReg(INIT_SWEEP);
-        wait_ms(5);
-        firstMeasurement = false;
-        return getData();
-    } else if(increment) {
+    if(increment) {
         setControlReg(INCR_FREQ);
-        wait_ms(5);
+        wait_us(WAITTIME);
         return getData();
     } else {
+        setControlReg(0x00);
         setControlReg(REPE_FREQ);
-        wait_ms(5);
+        wait_us(WAITTIME);
         return getData();
     }
 }
@@ -201,7 +219,7 @@
     bool output;
 
     while(((getRegister(0x8F) & 0x02)  != 0x02) && i < 10) {
-        wait_ms(50);
+        wait_us(500);
         i++;
     }
     if(i == 10)
@@ -218,12 +236,12 @@
 {
     int i = 0;
     uint8_t data[2];
-    
+
     setControlReg(MEAS_TEMP);
-    wait_ms(5);
+    wait_us(WAITTIME);
 
     while(((getRegister(0x8F) & 0x01) != 0x01) && i < 10) {
-        wait_ms(5);
+        wait_us(500);
         i++;
     }
     if(i == 10)

--- a/ad5933.h	Wed May 13 14:07:40 2015 +0000
+++ b/ad5933.h	Wed May 20 09:17:24 2015 +0000
@@ -12,6 +12,7 @@
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
+   
  --------------------------------------------------------------------------------- */
 
 #ifndef MBED_AD5933_H
@@ -21,6 +22,31 @@
 
 /** AD5933 class.
  *  Library to communicate with the AD5933 impedance meter chip.
+ *
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "ad5933.h"
+ *
+ * AD5933 Zmeter(p28, p27, false);
+ *
+ * int main() {
+ *     float temp = Zmeter.getTemperature();
+ *
+ *     Zmeter.initFrequencySweepParam(100000, 10, 2, 50, true, 1);
+ *
+ *     while(true) {
+ *          if(!Zmeter.Measure(true))
+ *              printf("error occured");
+ *          
+ *          int real = Zmeter.real;
+ *          int imag = Zmeter.imaginary;
+ *
+ *          wait(1);
+ *     }
+ *     
+ * }
+ * @endcode
  */
 class AD5933
 {
@@ -31,50 +57,64 @@
     @param extClk source of the Clock signal:  true = external;  false = internal
     */
     AD5933(PinName sda, PinName scl, bool extClk);
-    
-    /** Set all parameters concerning a frequency sweep.
-    @param startFreq initial frequency (max 100000Hz)
-    @param stepFreq stepsize of increment in frequency
-    @param nrOfSteps number of increments
-    */    
-    bool setFrequencySweepParam(unsigned int startFreq, unsigned int stepFreq, unsigned int nrOfSteps);
-    
+
     /** Time to wait before the ADC starts to sample
     @param nrOfCycles Number of cycles (outputfrequency) to wait for sampling can start  (max 2044)
-    */    
+    @return true on succes, false on failure
+    */
     bool setSettlingTime(unsigned int nrOfCycles);
-    
+
     /** Set the gain of the pre-amplification and the output voltage range
     @param PGA Gain of the pre-amplifier (true = x1; false = x5)
     @param RangeNr Set the output voltage (1 = 2V; 2 = 1V; 3 = 400mV; 4 = 200mV)
-    */ 
+    @return true on succes, false on failure
+    */
     bool setAnalogCircuit(bool PGA, int RangeNr);
-    
+
     /** Measure Impedance
     @param increment (true = goto next frequency in sweep; false = remeasure at current frequency)
-    */     
+    @return true on succes, false on failure
+    */
     bool Measure(bool increment);
-    
+
     /// Resets Device
+    ///@return true on succes, false on failure
     bool reset();
-    
+
     /// Get temperature of chip
+    ///@return temperature in degrees Celcius
     float getTemperature();
-    
+
+    /// Puts the Device in Standby Mode
+    ///@return true on succes, false on failure
     bool standby();
-    
+
+    /// Puts the Device in PowerDown Mode
+    ///@return true on succes, false on failure
+    bool powerdown();
+
+    /** Initialises a frequency sweep.
+    @param startFreq initial frequency (max 100000Hz)
+    @param stepFreq stepsize of increment in frequency
+    @param nrOfSteps number of increments
+    @param nrOfCycles Number of cycles (outputfrequency) to wait for sampling can start  (max 2044)
+    @param PGA Gain of the pre-amplifier (true = x1; false = x5)
+    @param RangeNr Set the output voltage (1 = 2V; 2 = 1V; 3 = 400mV; 4 = 200mV)
+    @return true on succes, false on failure
+    */
+    bool initFrequencySweepParam(unsigned int startFreq, unsigned int stepFreq, unsigned int nrOfSteps, unsigned int nrOfCycles, bool PGA, int RangeNr);
+
     /// real part of impedance (uncalibrated)
     unsigned int real;
-    
+
     /// imaginary part of impedance (uncalibrated)
     unsigned int imaginary;
-    
-    
+
 private:
     I2C sCom;
     uint8_t PGAandVoltout;
-    bool firstMeasurement;
 
+    bool setFrequencySweepParam(unsigned int startFreq, unsigned int stepFreq, unsigned int nrOfSteps);
     bool gotoAdressPointer(uint8_t Adress);
     bool setRegister(uint8_t RegisterAdress, uint8_t RegisterValue);
     bool writeBlock(uint8_t ByteArray[], uint8_t sizeArray);