Diff: main.cpp

Revision:

0:d66d4aaa919f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Mar 14 18:10:31 2019 +0000
@@ -0,0 +1,162 @@
+#include "mbed.h"
+
+#define IrThermo_Addr (0x5A<<1)
+#define Tamb 0x06
+#define Tobj 0x07
+
+I2C i2c(D14, D15);
+DigitalOut myled(LED1);
+Serial console(SERIAL_TX, SERIAL_RX);
+
+int temperature=0;
+char data_read[2];
+char data_write[1]= {Tobj};
+char data_add[1]= {(0x2E)};
+
+void changeAddress()
+{
+    //char newAddr[2]= {0x5E,0x00};
+    char p1,p2;
+    bool ch,ch2,ch3;
+    
+    //----read address to make sure it worked------------
+
+    // send start bit
+    i2c.start();
+    // send universal address
+    ch = i2c.write(0x00);
+    // prints if sensor acknowledges
+    if (!ch) console.printf("no ack\n");
+    else console.printf("ack\n");
+    // send EEPROM slave location address
+    ch2 = i2c.write(0x2E);
+    // send repeated start
+    i2c.start();
+    // send universal address 0x00 (seven bit) and use 1 as the eight bit -> 0x01
+    i2c.write(0x01); // last bit 1 indicates read request
+    // read LSB
+    p1 = i2c.read(1);
+    // read MSB
+    p2 = i2c.read(1);
+    // read PEC
+    i2c.read(0);
+    // release the bus
+    i2c.stop();
+    wait(0.1);
+    // print hex
+    console.printf("0x%x%x\nMSB 0x%x, LSB 0x%x\n", p2, p1, p2, p1);
+    wait(10);
+    
+    
+    // make sure i2c is inactive
+    i2c.stop();
+    wait(0.1);
+    //send start bit
+    i2c.start();
+    // address the sensor using universal address 0x00 not its default 0x5A
+    ch = i2c.write(0x00); // last bit 0 indicates write
+    // prints if sensor acknowledges
+    if (!ch) {
+        console.printf("no ack\n");
+    } else console.printf("ack 0x00\n");
+    // write command
+    // EEPROM address. Datasheet says 0x0E BUT!!! accessing EEPROM requires ading 0x20. Hence, 0x2E
+    ch2 = i2c.write(0x2E);
+    // prints if sensor acknowledges
+    if (!ch2) console.printf("no ack address location\n");
+    console.printf("ack 0x0E\n");
+    // delete old address
+    // LSB
+    i2c.write(0x00);
+    // MSB
+    i2c.write(0x00);
+    // use CRC-8 calculator to obtain PEC bit http://www.sunshine2k.de/coding/javascript/crc/crc_js.html
+    // I send 2E0000 --> PEC 0x6F
+    ch3 = i2c.write(0x6F);
+    // prints if sensor acknowledges
+    if(!ch3) console.printf("no PEC\n");
+    else console.printf("PEC success\n");
+    // release the bus
+    i2c.stop();
+    wait(1);
+
+//-----set new address----------------
+
+    // send start bit
+    i2c.start();
+    // send universal device address 0x00
+    i2c.write(0x00);
+    // prints if sensor acknowledges
+    if (!ch) console.printf("no ack\n");
+    else console.printf("ack\n");
+    // send EEPROM location for slave address
+    ch2 = i2c.write(0x2E);
+    // prints if sensor acknowledges
+    if (!ch2) console.printf("no ack slave address location\n");
+    else console.printf("ack 2\n");
+    //write new address anything between 0x0000 and 0x007F (default 0x5A, PEC 0xE1)
+    // LSB
+    i2c.write(0x04);
+    // MSB
+    i2c.write(0x00);
+    // send PEC calculated from CRC-8
+    // I send 2E0400 -> PEC 0x3B
+    i2c.write(0x3B);
+    // release the bus
+    i2c.stop();
+    wait(1);
+
+//----read address to make sure it worked------------
+
+    // send start bit
+    i2c.start();
+    // send universal address
+    ch = i2c.write(0x00);
+    // prints if sensor acknowledges
+    if (!ch) console.printf("no ack\n");
+    else console.printf("ack\n");
+    // send EEPROM slave location address
+    ch2 = i2c.write(0x2E);
+    // send repeated start
+    i2c.start();
+    // send universal address 0x00 (seven bit) and use 1 as the eight bit -> 0x01
+    i2c.write(0x01); // last bit 1 indicates read request
+    // read LSB
+    p1 = i2c.read(1);
+    // read MSB
+    p2 = i2c.read(1);
+    // read PEC
+    i2c.read(0);
+    // release the bus
+    i2c.stop();
+    wait(0.1);
+    // print hex
+    console.printf("0x%x%x\nMSB 0x%x, LSB 0x%x\n", p2, p1, p2, p1);
+    wait(10);
+}
+
+int main()
+{
+    console.printf("IrThermo Test\n");
+    i2c.write(IrThermo_Addr, data_add, 1, 1);
+    i2c.read(IrThermo_Addr, data_read, 2, 0);
+    console.printf("Sensor Address: %x\n",data_read[0]);
+    //changeAddress();
+    
+    while(1) {
+        i2c.write(IrThermo_Addr, data_write, 1, 1);
+        i2c.read(IrThermo_Addr, data_read, 2, 0);
+
+        console.printf("Raw Data: %x %x\n",(data_read[0]), (data_read[1]));
+        temperature = (int) ((int)data_read[1] << 8) | data_read[0];
+        temperature = (temperature * 0.02 - 273.15);
+        if (data_write[0]==Tamb) {
+            console.printf("Ambient temperature= %d\n", temperature);
+        } else {
+            console.printf("Object temperature= %d\n", temperature);
+        }
+        myled = !myled;
+        wait(1.0);
+    }
+    
+}