Revision 1:d0f691423bf1, committed 2011-04-23

Comitter:

ssozonoff

Date:

Sat Apr 23 18:10:56 2011 +0000

Parent:

0:74df6ab91c79

Child:

2:2464fed17980

Commit message:

Got Master Hold mode working, Thanks Andy!

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SHT21_I2C.h	Sat Apr 23 18:10:56 2011 +0000
@@ -0,0 +1,78 @@
+/*
+    Copyright (c) 2010 Andy Kirkham
+ 
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+ 
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+ 
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+*/
+
+#include "mbed.h"
+
+#ifndef SHT21_I2C_H
+#define SHT21_I2C_H
+
+class SHT_I2C : public I2C {
+
+protected:
+    PinName _scl;
+    PinName _sda;
+    
+public:
+
+    SHT_I2C(PinName sda, PinName scl, const char *name = NULL) : I2C(sda, scl, name) {
+        _sda = sda;
+        _scl = scl;
+    }
+    
+    void sclAsInput(void) {
+        switch(_scl) {
+            case p10:
+                LPC_PINCON->PINSEL0 &= ~(3UL << 2); // p10, P0.1 as GPIO
+                LPC_GPIO0->FIODIR &= ~(1UL << 1);   // p10, P0.1 as Input
+                break;
+            case p27:
+                LPC_PINCON->PINSEL0&=~(3UL << 22);  // p27, P0.11 as GPIO
+                LPC_GPIO0->FIODIR &= ~(1UL << 11);  // p27, P0.11 as input
+                break;                
+        }
+    }
+    
+    int sclRead(void) {
+        switch(_scl) {
+            case p10: return (LPC_GPIO0->FIOPIN & (1UL <<  1)) ? 1 : 0;
+            case p27: return (LPC_GPIO0->FIOPIN & (1UL << 11)) ? 1 : 0;                
+            default:
+                return 0;
+        }
+    }
+    
+    void sclNormal(void) {
+        switch(_scl) {
+            case p10:
+                LPC_PINCON->PINSEL0 &= ~(3UL << 2); // p10, P0.1 as I2C SCL1
+                LPC_PINCON->PINSEL0 |=  (3UL << 2);
+                break;
+            case p27:
+                LPC_PINCON->PINSEL0 &= ~(3UL << 22); // p27, P0.11 as I2C SCL2
+                LPC_PINCON->PINSEL0 |=  (2UL << 22);            
+                break;                
+        }
+    }
+
+};
+
+#endif
\ No newline at end of file

--- a/SHT2x.cpp	Sat Apr 23 14:08:11 2011 +0000
+++ b/SHT2x.cpp	Sat Apr 23 18:10:56 2011 +0000
@@ -10,11 +10,9 @@
 //==============================================================================//
 //---------- Includes ----------------------------------------------------------
 #include "SHT2x.h"
+#include "mbed.h"
 
-SHT2x::SHT2x (PinName p_sda, PinName p_scl) : i2c(p_sda, p_scl) {
-}
-
-SHT2x::SHT2x (I2C& p_i2c) : i2c(p_i2c) { 
+SHT2x::SHT2x (PinName p_sda, PinName p_scl) : i2c(p_sda, p_scl), out(USBTX, USBRX)  {
 }
 
 //==============================================================================//
@@ -40,19 +38,19 @@
 {
     int checksum;   //variable for checksum byte
     int error=0;    //variable for error code
-    
+
     i2c.start();
     i2c.write(I2C_ADR_W);
     i2c.write(USER_REG_R);
-    
+
     i2c.start();
     i2c.write(I2C_ADR_R);
-        
-        
-    *pRegisterValue = i2c.read(1);
-    
-    checksum=i2c.read(0);
-    
+
+
+    *pRegisterValue = i2c.read(ACK);
+
+    checksum=i2c.read(NoACK);
+
     error |= SHT2x_CheckCrc (pRegisterValue,1,checksum);
 
     i2c.stop();
@@ -64,7 +62,7 @@
 {
     int error=0;   //variable for error code
     i2c.start();
-    
+
     i2c.write(I2C_ADR_W);
     i2c.write(USER_REG_W);
     i2c.write(*pRegisterValue);
@@ -79,43 +77,48 @@
     int  checksum;   //checksum
     int  data[2];    //data array for checksum verification
     int  error=0;    //error variable
-    
-    //-- write I2C sensor address and command --    
+    int i;
+
+    //-- write I2C sensor address and command --
     i2c.start();
-       
+
     i2c.write(I2C_ADR_W); // I2C Adr
     switch (eSHT2xMeasureType) {
         case HUMIDITY:
             i2c.write(TRIG_RH_MEASUREMENT_HM);
             break;
-        case TEMP    :
+        case TEMP:
             i2c.write(TRIG_T_MEASUREMENT_HM);
             break;
         default:
             break;
     }
+    
     //-- wait until hold master is released --
-    i2c.start();    
+    i2c.start();
     i2c.write(I2C_ADR_R);
-    
+
     //SCL=HIGH;                     // set SCL I/O port as input
-    
-    //for (i=0; i<1000; i++) {      // wait until master hold is released or
-    //    DelayMicroSeconds(1000);    // a timeout (~1s) is reached
-    //    if (SCL_CONF==1) break;
-    //}
-    
+    i2c.sclAsInput();
+
+    for (i=0; i<1000; i++) {      // wait until master hold is released or
+        wait_ms(1);    // a timeout (~1s) is reached
+        if (i2c.sclRead() == 1) break;
+    }
+
     //-- check for timeout --
-    //if (SCL_CONF==0) error |= TIME_OUT_ERROR;
-//-- read two data bytes and one checksum byte --
+    if (i2c.sclRead() == 0) error |= TIME_OUT_ERROR;
+    //-- read two data bytes and one checksum byte --
 
-    data[0] = i2c.read(1);
-    data[1] = i2c.read(1);
-    
+    i2c.sclNormal();
+
+    data[0] = i2c.read(ACK);
+    data[1] = i2c.read(ACK);
+
     *pMeasurand = data[0] << 8;
     *pMeasurand |= data[1];
-    
-    checksum = i2c.read(0);
+
+    checksum = i2c.read(NoACK);
     //-- verify checksum --
     error |= SHT2x_CheckCrc (data, 2, checksum);
 
@@ -133,7 +136,7 @@
 
     //-- write I2C sensor address and command --
     i2c.start();
-    
+
     i2c.write(I2C_ADR_W);
     switch (eSHT2xMeasureType) {
         case HUMIDITY:
@@ -144,25 +147,25 @@
             break;
         default:
             break;
-            
+
     }
     //-- poll every 10ms for measurement ready. Timeout after 20 retries (200ms)--
     do {
         i2c.start();
-        wait_ms(10);        
+        wait_ms(10);
         if (i++ >= 20) break;
     } while (i2c.write(I2C_ADR_R) == 0);
-    
+
     if (i >= 20) error |= TIME_OUT_ERROR;
-    
+
     //-- read two data bytes and one checksum byte --
-    data[0] = i2c.read(1);
-    data[1] = i2c.read(1);
-    
+    data[0] = i2c.read(ACK);
+    data[1] = i2c.read(ACK);
+
     *pMeasurand = data[0] << 8;
-    *pMeasurand |= data[1];    
-    
-    checksum = i2c.read(0);
+    *pMeasurand |= data[1];
+
+    checksum = i2c.read(NoACK);
     //-- verify checksum --
     error |= SHT2x_CheckCrc (data,2,checksum);
     i2c.stop();
@@ -196,7 +199,7 @@
 {
     float temperatureC;            // variable for result
     u16sT &= ~0x0003;           // clear bits [1..0] (status bits)
-    //-- calculate temperature [°C] --
+    //-- calculate temperature [�C] --
     temperatureC= -46.85 + 175.72/65536 *(float)u16sT; //T= -46.85 + 175.72 * ST/2^16
     return temperatureC;
 }
@@ -205,21 +208,21 @@
 //==============================================================================//
 {
     int  error=0;                          //error variable
-    //Read from memory location 1   
+    //Read from memory location 1
     i2c.start();
-    error |= i2c.write(I2C_ADR_W);   
+    error |= i2c.write(I2C_ADR_W);
     error |= i2c.write(0xFA);         //Command for readout on-chip memory
     error |= i2c.write(0x0F);         //on-chip memory address
     i2c.start();
     error |= i2c.write(I2C_ADR_R);    //I2C address
-    u8SerialNumber[5] = i2c.read(1); //Read SNB_3
-    i2c.read(1);                     //Read CRC SNB_3 (CRC is not analyzed)
-    u8SerialNumber[4] = i2c.read(1); //Read SNB_2
-    i2c.read(1);                     //Read CRC SNB_2 (CRC is not analyzed)
-    u8SerialNumber[3] = i2c.read(1); //Read SNB_1Sample Code SHT21
-    i2c.read(1);                     //Read CRC SNB_1 (CRC is not analyzed)
-    u8SerialNumber[2] = i2c.read(1); //Read SNB_0
-    i2c.read(0);                  //Read CRC SNB_0 (CRC is not analyzed)
+    u8SerialNumber[5] = i2c.read(ACK); //Read SNB_3
+    i2c.read(ACK);                     //Read CRC SNB_3 (CRC is not analyzed)
+    u8SerialNumber[4] = i2c.read(ACK); //Read SNB_2
+    i2c.read(ACK);                     //Read CRC SNB_2 (CRC is not analyzed)
+    u8SerialNumber[3] = i2c.read(ACK); //Read SNB_1Sample Code SHT21
+    i2c.read(ACK);                     //Read CRC SNB_1 (CRC is not analyzed)
+    u8SerialNumber[2] = i2c.read(ACK); //Read SNB_0
+    i2c.read(NoACK);                  //Read CRC SNB_0 (CRC is not analyzed)
     i2c.stop();
     //Read from memory location 2
     i2c.start();
@@ -228,12 +231,12 @@
     error |= i2c.write(0xC9);         //on-chip memory address
     i2c.start();
     error |= i2c.write(I2C_ADR_R);    //I2C address
-    u8SerialNumber[1] = i2c.read(1); //Read SNC_1
-    u8SerialNumber[0] = i2c.read(1); //Read SNC_0
-    i2c.read(1);
-    u8SerialNumber[7] = i2c.read(1); //Read SNA_1
-    u8SerialNumber[6] = i2c.read(1); //Read SNA_0
-    i2c.read(0);                  //Read CRC SNA0/1 (CRC is not analyzed)
+    u8SerialNumber[1] = i2c.read(ACK); //Read SNC_1
+    u8SerialNumber[0] = i2c.read(ACK); //Read SNC_0
+    i2c.read(ACK);
+    u8SerialNumber[7] = i2c.read(ACK); //Read SNA_1
+    u8SerialNumber[6] = i2c.read(ACK); //Read SNA_0
+    i2c.read(NoACK);                  //Read CRC SNA0/1 (CRC is not analyzed)
     i2c.stop();
     return error;
 }
\ No newline at end of file

--- a/SHT2x.h	Sat Apr 23 14:08:11 2011 +0000
+++ b/SHT2x.h	Sat Apr 23 18:10:56 2011 +0000
@@ -1,4 +1,5 @@
 #include "mbed.h"
+#include "SHT21_I2C.h"
 
 #ifndef SHT2x_H
 #define SHT2x_H
@@ -16,6 +17,9 @@
 //  CRC
 
 const int POLYNOMIAL = 0x131;  //P(x)=x^8+x^5+x^4+1 = 100110001
+const int ACK = 1;
+const int NoACK = 0;
+
 // sensor command
 enum etSHT2xCommand {
     TRIG_T_MEASUREMENT_HM    = 0xE3, // command trig. temp meas. hold master
@@ -68,7 +72,6 @@
 class SHT2x : public Base {
 public:
     SHT2x (PinName p_sda, PinName p_scl);
-    SHT2x (I2C& p_i2c);
 
     int SHT2x_CheckCrc(int data[], int nbrOfBytes, int checksum);
     int SHT2x_ReadUserRegister(int *pRegisterValue);
@@ -81,7 +84,8 @@
     int SHT2x_GetSerialNumber(int u8SerialNumber[]);
 
 protected:
-    I2C i2c;
+    SHT_I2C i2c;
+    Serial out;
 
 private: