(DA) Internet of Things and Smart Electronics- ELE3006M2122 / Mbed 2 deprecated Final_Project_V19_DLeaming_25574043

Final tidy of code following installation of new sensor, more comments added prior to submission

Dependencies:   mbed

TMP102/TMP102.cpp@18:fc63b51a0302, 2022-02-04 (annotated)

Committer:
legstar85
Date:
Fri Feb 04 09:20:18 2022 +0000
Revision:
18:fc63b51a0302
Parent:
13:5ad65a688f3f 
Final tidy of code following installation of new sensor, more comments added prior to submission

Who changed what in which revision?

UserRevisionLine numberNew contents of line
legstar85 13:5ad65a688f3f 1 /* * Print String
legstar85 13:5ad65a688f3f 2 *
legstar85 13:5ad65a688f3f 3 * Prints a string of characters to the screen buffer, string is cut off after the 83rd pixel.
legstar85 13:5ad65a688f3f 4 * @param x - the column number (0 to 83)
legstar85 13:5ad65a688f3f 5 * @param y - the row number (0-5) - the display is split into 6 banks - each bank can be considered a row
legstar85 13:5ad65a688f3f 6 * @author - David Leaming - 25574043
legstar85 13:5ad65a688f3f 7 * @ Date - December 2021
legstar85 13:5ad65a688f3f 8 *
legstar85 13:5ad65a688f3f 9 * Acknowledgements
legstar85 13:5ad65a688f3f 10 * Craig A. Evans, University of Leeds, TMP102 Library ,Feb 2016
legstar85 13:5ad65a688f3f 11 * Dr Edmond Nurellari, University of Lincoln, Joystick & N5110 Libraries
legstar85 13:5ad65a688f3f 12 *
legstar85 13:5ad65a688f3f 13 */
legstar85 13:5ad65a688f3f 14
legstar85 13:5ad65a688f3f 15 // library implemtation file
legstar85 13:5ad65a688f3f 16
legstar85 13:5ad65a688f3f 17 // obviously need to include the header
legstar85 13:5ad65a688f3f 18 #include "TMP102.h"
legstar85 13:5ad65a688f3f 19
legstar85 13:5ad65a688f3f 20 // we now implement each of the methods listed in the header
legstar85 13:5ad65a688f3f 21
legstar85 13:5ad65a688f3f 22 // note the TMP102:: at the beginning of the method name
legstar85 13:5ad65a688f3f 23 TMP102::TMP102(PinName sda, PinName scl)
legstar85 13:5ad65a688f3f 24 {
legstar85 13:5ad65a688f3f 25 // in the constructor, we create the mbed API objects using 'new'
legstar85 13:5ad65a688f3f 26 i2c_ = new I2C(sda,scl);
legstar85 13:5ad65a688f3f 27 led_ = new DigitalOut(LED_RED);
legstar85 13:5ad65a688f3f 28 }
legstar85 13:5ad65a688f3f 29
legstar85 13:5ad65a688f3f 30 void TMP102::init()
legstar85 13:5ad65a688f3f 31 {
legstar85 13:5ad65a688f3f 32 i2c_->frequency(400000); // set bus speed to 400 kHz
legstar85 13:5ad65a688f3f 33
legstar85 13:5ad65a688f3f 34 int ack; // used to store acknowledgement bit
legstar85 13:5ad65a688f3f 35 char config_data[2]; // array for data
legstar85 13:5ad65a688f3f 36 char reg = CONFIG_REG; // register address
legstar85 13:5ad65a688f3f 37
legstar85 13:5ad65a688f3f 38 //////// Read current status of configuration register ///////
legstar85 13:5ad65a688f3f 39
legstar85 13:5ad65a688f3f 40 ack = i2c_->write(TMP102_W_ADD,&reg,1); // send the slave write address and the configuration register address
legstar85 13:5ad65a688f3f 41 if (ack)
legstar85 13:5ad65a688f3f 42 error(); // if we don't receive acknowledgement, flash error message
legstar85 13:5ad65a688f3f 43
legstar85 13:5ad65a688f3f 44 ack = i2c_->read(TMP102_R_ADD,config_data,2); // read default 2 bytes from configuration register and store in array
legstar85 13:5ad65a688f3f 45 if (ack)
legstar85 13:5ad65a688f3f 46 error(); // if we don't receive acknowledgement, flash error message
legstar85 13:5ad65a688f3f 47
legstar85 13:5ad65a688f3f 48 ///////// Configure the register //////////
legstar85 13:5ad65a688f3f 49
legstar85 13:5ad65a688f3f 50 // set conversion rate to 1 Hz - CR1 and CR2 are in the second data byte
legstar85 13:5ad65a688f3f 51 config_data[1] |= (1 << 6); // set bit 6
legstar85 13:5ad65a688f3f 52 config_data[1] &= ~(1 << 7); // clear bit 7
legstar85 13:5ad65a688f3f 53
legstar85 13:5ad65a688f3f 54 //////// Send the configured register value to the slave config register ////////////
legstar85 13:5ad65a688f3f 55
legstar85 13:5ad65a688f3f 56 // create data packet
legstar85 13:5ad65a688f3f 57 char data_packet[3] = {reg,config_data[0],config_data[1]};
legstar85 13:5ad65a688f3f 58
legstar85 13:5ad65a688f3f 59 ack = i2c_->write(TMP102_W_ADD,data_packet,3); // send the data packet to the slave write address
legstar85 13:5ad65a688f3f 60 if (ack)
legstar85 13:5ad65a688f3f 61 error(); // if we don't receive acknowledgement, flash error message
legstar85 13:5ad65a688f3f 62
legstar85 13:5ad65a688f3f 63 }
legstar85 13:5ad65a688f3f 64
legstar85 13:5ad65a688f3f 65 void TMP102::read_temperature()
legstar85 13:5ad65a688f3f 66 {
legstar85 13:5ad65a688f3f 67 int ack; // used to store acknowledgement bit
legstar85 13:5ad65a688f3f 68 char data[2]; // array for data
legstar85 13:5ad65a688f3f 69 char reg = TEMP_REG; // temperature register address
legstar85 13:5ad65a688f3f 70
legstar85 13:5ad65a688f3f 71 ack = i2c_->write(TMP102_W_ADD,&reg,1); // send temperature register address
legstar85 13:5ad65a688f3f 72 if (ack)
legstar85 13:5ad65a688f3f 73 error(); // if we don't receive acknowledgement, flash error message
legstar85 13:5ad65a688f3f 74
legstar85 13:5ad65a688f3f 75 ack = i2c_->read(TMP102_R_ADD,data,2); // read 2 bytes from temperature register and store in array
legstar85 13:5ad65a688f3f 76 if (ack)
legstar85 13:5ad65a688f3f 77 error(); // if we don't receive acknowledgement, flash error message
legstar85 13:5ad65a688f3f 78
legstar85 13:5ad65a688f3f 79 int temperature = (data[0] << 4) | (data[1] >> 4);
legstar85 13:5ad65a688f3f 80
legstar85 13:5ad65a688f3f 81 temperature_ = temperature*0.0625F;
legstar85 13:5ad65a688f3f 82 }
legstar85 13:5ad65a688f3f 83
legstar85 13:5ad65a688f3f 84 // temperature accessor method
legstar85 13:5ad65a688f3f 85 float TMP102::get_temperature()
legstar85 13:5ad65a688f3f 86 {
legstar85 13:5ad65a688f3f 87 read_temperature();
legstar85 13:5ad65a688f3f 88 return temperature_;
legstar85 13:5ad65a688f3f 89 }
legstar85 13:5ad65a688f3f 90
legstar85 13:5ad65a688f3f 91 void TMP102::error()
legstar85 13:5ad65a688f3f 92 {
legstar85 13:5ad65a688f3f 93 while(1) { // if error, hang while flashing error message
legstar85 13:5ad65a688f3f 94 led_->write(0);
legstar85 13:5ad65a688f3f 95 wait(0.2);
legstar85 13:5ad65a688f3f 96 led_->write(1);
legstar85 13:5ad65a688f3f 97 wait(0.2);
legstar85 13:5ad65a688f3f 98 }
legstar85 13:5ad65a688f3f 99 }