Diff: HY3116.cpp

Revision:

0:80768ca5d5ff

Child:

1:1967c3f48465

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/HY3116.cpp	Wed May 11 12:11:43 2016 +0000
@@ -0,0 +1,93 @@
+#include "HY3116.h"
+
+// Define I2C pins (SDA,SCL)
+static I2C i2c(p30,p7); // nRF51-DK
+
+// Single-byte write helper function
+void HY3116::writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
+{
+    char data_write[2];
+    data_write[0]=subAddress;           // I2C sends MSB first. Namely  >>|subAddress|>>|data|
+    data_write[1]=data;
+    i2c.write(address,data_write,2,0);  // i2c.write(int address, char* data, int length, bool repeated=false);  
+}
+
+// Function to send the reset command
+void HY3116::resetChip()
+{
+    char data_write[1];
+    data_write[0]=RESET;
+    i2c.write(HY3116_ADDRESS,data_write,1,0);  // i2c.write(int address, char* data, int length, bool repeated=false);  
+}
+
+// Multi-byte read helper function
+void HY3116::readBytes(uint8_t address, uint8_t subAddress, uint8_t byteNum, uint8_t* dest, bool alreadyRead)
+{
+    char data[14],data_write[1];  
+    data_write[0]=subAddress;
+    if (!alreadyRead) {     
+        i2c.write(address,data_write,1,1);
+    }
+    i2c.read(address,data,byteNum,0);
+    for(int i=0;i<byteNum;i++)         // equate the addresses
+        dest[i]=data[i];
+}
+
+// Dedicated ADC-output read, check & format function
+int32_t HY3116::readAdc(bool alreadyRead)
+{
+    uint8_t rawData[3];
+    bool newReading = 0;
+    int32_t adcReading = 0;
+    
+    readBytes(HY3116_ADDRESS, ADO, 3, &rawData[0], alreadyRead);
+    
+    if (rawData[2] & 0b00000001) {
+        newReading = 1;
+    }
+    else {
+        newReading = 0;
+    }
+    
+    adcReading += rawData[0] << 15;
+    adcReading += rawData[1] << 7;
+    adcReading += rawData[2] >> 1;
+    
+    // Account for twos complement polarity
+    if (rawData[0] & 0b10000000) {
+        adcReading ^= 0xFF800000;
+    }
+    
+    return adcReading;
+}
+
+// Initialise the HY3116 with the following config.:
+//
+void HY3116::init()
+{
+    // Set the I2C clock frequency
+    i2c.frequency(100000);
+    
+    // Set-up the SYS register
+    writeByte(HY3116_ADDRESS, SYS, 0b00011100); // Enable the ADC & LDO
+    wait_ms(100); // wait 100 ms to stabilize 
+        
+    // Set-up the ADC1 register
+    writeByte(HY3116_ADDRESS, ADC1, 0b00001000); // Set inputs to AIN1 & AIN2
+    wait_ms(100); // wait 100 ms to stabilize
+    
+    // Set-up the ADC2 register
+    writeByte(HY3116_ADDRESS, ADC2, 0b01010000); // Set pos. ref. voltage to VDDA, neg. ref. to VSSA, DC offset to 0VRef
+    wait_ms(100); // wait 100 ms to stabilize
+    
+    // Set-up the ADC3 register
+    writeByte(HY3116_ADDRESS, ADC3, 0b01111100); // Set to int. osc. 327kHz, full ref. range, PGA to 32x, pre-amp to 1x
+    wait_ms(100); // wait 100 ms to stabilize
+    
+    // Set-up the ADC4 register
+    writeByte(HY3116_ADDRESS, ADC4, 0b01011110); // Set LDO to 3.0V, REFO = 1.2V, conv. rate = 327kHz, SPS = 40
+    wait_ms(100); // wait 100 ms to stabilize
+    
+    resetChip();
+    wait_ms(500);
+}
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