Library to interface the SCP1000 temperature and pressure sensor.

Dependents:   SCP1000_Example ku-make_sensor ku-make_sensor201302 SCP1000_Example ... more

Committer:
kadams6
Date:
Tue Oct 05 04:10:55 2010 +0000
Revision:
1:5fcf1fe4a161
Parent:
0:0b8b5828e1a3
Child:
2:fe7826024fd1

        

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kadams6 0:0b8b5828e1a3 1 #ifndef _SCP1000_H
kadams6 0:0b8b5828e1a3 2 #define _SCP1000_H
kadams6 0:0b8b5828e1a3 3
kadams6 0:0b8b5828e1a3 4 #include "mbed.h"
kadams6 0:0b8b5828e1a3 5
kadams6 0:0b8b5828e1a3 6 class SCP1000 {
kadams6 0:0b8b5828e1a3 7 public:
kadams6 0:0b8b5828e1a3 8 SCP1000(PinName mosi, PinName miso, PinName sclk, PinName cs)
kadams6 0:0b8b5828e1a3 9 : m_spi(mosi, miso, sclk)
kadams6 0:0b8b5828e1a3 10 , m_cs(cs) {
kadams6 0:0b8b5828e1a3 11 m_cs=1;
kadams6 0:0b8b5828e1a3 12 m_spi.frequency(500000); // the fastest of the sensor
kadams6 0:0b8b5828e1a3 13 m_spi.format(8, 0); // duda son dos palabras de 8 bits?
kadams6 0:0b8b5828e1a3 14 wait(0.5);
kadams6 0:0b8b5828e1a3 15 //------------------------------------------------
kadams6 0:0b8b5828e1a3 16 // pc.printf("RESET\r\n");
kadams6 0:0b8b5828e1a3 17 write_register(0x06,0x01);
kadams6 0:0b8b5828e1a3 18 wait(0.5);
kadams6 0:0b8b5828e1a3 19
kadams6 0:0b8b5828e1a3 20 // pc.printf("Initialize High Resolution Constant Reading Mode\r\n");
kadams6 0:0b8b5828e1a3 21 write_register(0x03,0x0A);
kadams6 0:0b8b5828e1a3 22 wait(0.5);
kadams6 0:0b8b5828e1a3 23 };
kadams6 0:0b8b5828e1a3 24
kadams6 0:0b8b5828e1a3 25 ~SCP1000() { /* empty */ };
kadams6 0:0b8b5828e1a3 26
kadams6 1:5fcf1fe4a161 27 /**
kadams6 1:5fcf1fe4a161 28 * Read the pressure in pascals.
kadams6 1:5fcf1fe4a161 29 *
kadams6 1:5fcf1fe4a161 30 * @return The pressure in pascals.
kadams6 1:5fcf1fe4a161 31 */
kadams6 0:0b8b5828e1a3 32 unsigned long readPressure() {
kadams6 0:0b8b5828e1a3 33 unsigned long pressure_msb = read_register(PRESSURE);
kadams6 0:0b8b5828e1a3 34 pressure_msb &= 0x07;
kadams6 0:0b8b5828e1a3 35 unsigned long pressure_lsb = read_register16(PRESSURE_LSB);
kadams6 0:0b8b5828e1a3 36 unsigned long pressure = ((pressure_msb<<16)| pressure_lsb);
kadams6 0:0b8b5828e1a3 37 pressure /= 4;
kadams6 0:0b8b5828e1a3 38
kadams6 0:0b8b5828e1a3 39 return pressure;
kadams6 0:0b8b5828e1a3 40 };
kadams6 0:0b8b5828e1a3 41
kadams6 0:0b8b5828e1a3 42 float readTemperature() {
kadams6 0:0b8b5828e1a3 43 float temp_in = read_register16(TEMP);
kadams6 0:0b8b5828e1a3 44 temp_in /= 20;
kadams6 0:0b8b5828e1a3 45 return temp_in;
kadams6 0:0b8b5828e1a3 46 };
kadams6 0:0b8b5828e1a3 47
kadams6 0:0b8b5828e1a3 48
kadams6 0:0b8b5828e1a3 49 private:
kadams6 0:0b8b5828e1a3 50 static const char PRESSURE = 0x1F; //Pressure 3 MSB
kadams6 0:0b8b5828e1a3 51 static const char PRESSURE_LSB = 0x20; //Pressure 16 LSB
kadams6 0:0b8b5828e1a3 52 static const char TEMP = 0x21; //16 bit temp
kadams6 0:0b8b5828e1a3 53 SPI m_spi;
kadams6 0:0b8b5828e1a3 54 DigitalOut m_cs;
kadams6 0:0b8b5828e1a3 55
kadams6 0:0b8b5828e1a3 56 char read_register(char register_name) {
kadams6 0:0b8b5828e1a3 57 register_name <<=2;
kadams6 0:0b8b5828e1a3 58 register_name &= 0xFC;
kadams6 0:0b8b5828e1a3 59 m_cs=0; //Select SPI device
kadams6 0:0b8b5828e1a3 60 m_spi.write(register_name); //Send register location
kadams6 0:0b8b5828e1a3 61 char register_value=m_spi.write(0x00);
kadams6 0:0b8b5828e1a3 62 m_cs=1;
kadams6 0:0b8b5828e1a3 63 return register_value;
kadams6 0:0b8b5828e1a3 64 };
kadams6 0:0b8b5828e1a3 65
kadams6 0:0b8b5828e1a3 66 void write_register(char register_name, char register_value) {
kadams6 0:0b8b5828e1a3 67 register_name <<= 2;
kadams6 0:0b8b5828e1a3 68 register_name |= 0x02; //le estamos diciendo que escriba
kadams6 0:0b8b5828e1a3 69 m_cs=0; //Select SPI device
kadams6 0:0b8b5828e1a3 70 m_spi.write(register_name); //Send register location
kadams6 0:0b8b5828e1a3 71 m_spi.write(register_value); //Send value to record into register
kadams6 0:0b8b5828e1a3 72 m_cs=1;
kadams6 0:0b8b5828e1a3 73 };
kadams6 0:0b8b5828e1a3 74
kadams6 0:0b8b5828e1a3 75 float read_register16(char register_name) {
kadams6 0:0b8b5828e1a3 76 register_name <<= 2;
kadams6 0:0b8b5828e1a3 77 register_name &= 0xFC; //Read command
kadams6 0:0b8b5828e1a3 78 m_cs=0; //Select SPI Device
kadams6 0:0b8b5828e1a3 79 m_spi.write(register_name); //Write byte to device
kadams6 0:0b8b5828e1a3 80 int in_byte1 = m_spi.write(0x00);
kadams6 0:0b8b5828e1a3 81 int in_byte2 = m_spi.write(0x00);
kadams6 0:0b8b5828e1a3 82 m_cs=1;
kadams6 0:0b8b5828e1a3 83 float in_word= (in_byte1<<=8) | (in_byte2);
kadams6 0:0b8b5828e1a3 84 return(in_word);
kadams6 0:0b8b5828e1a3 85 };
kadams6 0:0b8b5828e1a3 86
kadams6 0:0b8b5828e1a3 87 };
kadams6 0:0b8b5828e1a3 88
kadams6 0:0b8b5828e1a3 89 #endif // _SCP1000_H