CJ Shaw / HY3116

Library for working with the HYCON HY3116/8 24-bit weigh-scales ADC series.

HY3116.cpp@2:2da9fbab02b7, 2016-06-13 (annotated)

Committer:
seajayshore
Date:
Mon Jun 13 00:43:19 2016 +0000
Revision:
2:2da9fbab02b7
Parent:
1:1967c3f48465
Child:
3:535ed9a0ce59
June 12 - freeze for China trip

Who changed what in which revision?

UserRevisionLine numberNew contents of line
seajayshore 0:80768ca5d5ff 1 #include "HY3116.h"
seajayshore 0:80768ca5d5ff 2
seajayshore 0:80768ca5d5ff 3 // Define I2C pins (SDA,SCL)
seajayshore 2:2da9fbab02b7 4 static I2C i2c(p6,p5); // nRF51-DK
seajayshore 0:80768ca5d5ff 5
seajayshore 0:80768ca5d5ff 6 // Single-byte write helper function
seajayshore 0:80768ca5d5ff 7 void HY3116::writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
seajayshore 0:80768ca5d5ff 8 {
seajayshore 0:80768ca5d5ff 9 char data_write[2];
seajayshore 0:80768ca5d5ff 10 data_write[0]=subAddress; // I2C sends MSB first. Namely >>|subAddress|>>|data|
seajayshore 0:80768ca5d5ff 11 data_write[1]=data;
seajayshore 0:80768ca5d5ff 12 i2c.write(address,data_write,2,0); // i2c.write(int address, char* data, int length, bool repeated=false);
seajayshore 0:80768ca5d5ff 13 }
seajayshore 0:80768ca5d5ff 14
seajayshore 0:80768ca5d5ff 15 // Function to send the reset command
seajayshore 0:80768ca5d5ff 16 void HY3116::resetChip()
seajayshore 0:80768ca5d5ff 17 {
seajayshore 0:80768ca5d5ff 18 char data_write[1];
seajayshore 0:80768ca5d5ff 19 data_write[0]=RESET;
seajayshore 0:80768ca5d5ff 20 i2c.write(HY3116_ADDRESS,data_write,1,0); // i2c.write(int address, char* data, int length, bool repeated=false);
seajayshore 0:80768ca5d5ff 21 }
seajayshore 0:80768ca5d5ff 22
seajayshore 0:80768ca5d5ff 23 // Multi-byte read helper function
seajayshore 0:80768ca5d5ff 24 void HY3116::readBytes(uint8_t address, uint8_t subAddress, uint8_t byteNum, uint8_t* dest, bool alreadyRead)
seajayshore 0:80768ca5d5ff 25 {
seajayshore 0:80768ca5d5ff 26 char data[14],data_write[1];
seajayshore 0:80768ca5d5ff 27 data_write[0]=subAddress;
seajayshore 0:80768ca5d5ff 28 if (!alreadyRead) {
seajayshore 0:80768ca5d5ff 29 i2c.write(address,data_write,1,1);
seajayshore 0:80768ca5d5ff 30 }
seajayshore 0:80768ca5d5ff 31 i2c.read(address,data,byteNum,0);
seajayshore 0:80768ca5d5ff 32 for(int i=0;i<byteNum;i++) // equate the addresses
seajayshore 0:80768ca5d5ff 33 dest[i]=data[i];
seajayshore 0:80768ca5d5ff 34 }
seajayshore 0:80768ca5d5ff 35
seajayshore 0:80768ca5d5ff 36 // Dedicated ADC-output read, check & format function
seajayshore 1:1967c3f48465 37 bool HY3116::readAdc(int32_t *_adcReading)
seajayshore 0:80768ca5d5ff 38 {
seajayshore 1:1967c3f48465 39 // Initialise function variables
seajayshore 0:80768ca5d5ff 40 uint8_t rawData[3];
seajayshore 0:80768ca5d5ff 41 bool newReading = 0;
seajayshore 0:80768ca5d5ff 42 int32_t adcReading = 0;
seajayshore 0:80768ca5d5ff 43
seajayshore 1:1967c3f48465 44 // Change this to improve I2C speed slightly (see datasheet)
seajayshore 1:1967c3f48465 45 bool alreadyRead = 0;
seajayshore 1:1967c3f48465 46
seajayshore 1:1967c3f48465 47 // Read in the raw ADO bytes
seajayshore 0:80768ca5d5ff 48 readBytes(HY3116_ADDRESS, ADO, 3, &rawData[0], alreadyRead);
seajayshore 0:80768ca5d5ff 49
seajayshore 1:1967c3f48465 50 // Test if there is new data (polling mode)
seajayshore 0:80768ca5d5ff 51 if (rawData[2] & 0b00000001) {
seajayshore 1:1967c3f48465 52
seajayshore 1:1967c3f48465 53 // Set the newReading flag
seajayshore 0:80768ca5d5ff 54 newReading = 1;
seajayshore 1:1967c3f48465 55
seajayshore 1:1967c3f48465 56 // Shift the raw bytes into the 32-bit variable
seajayshore 1:1967c3f48465 57 adcReading += rawData[0] << 15;
seajayshore 1:1967c3f48465 58 adcReading += rawData[1] << 7;
seajayshore 1:1967c3f48465 59 adcReading += rawData[2] >> 1;
seajayshore 1:1967c3f48465 60
seajayshore 1:1967c3f48465 61 // Account for twos complement polarity
seajayshore 1:1967c3f48465 62 if (rawData[0] & 0b10000000) {
seajayshore 1:1967c3f48465 63 adcReading ^= 0xFF800000;
seajayshore 1:1967c3f48465 64 }
seajayshore 0:80768ca5d5ff 65 }
seajayshore 0:80768ca5d5ff 66 else {
seajayshore 1:1967c3f48465 67
seajayshore 1:1967c3f48465 68 // Set the newReading flag
seajayshore 0:80768ca5d5ff 69 newReading = 0;
seajayshore 0:80768ca5d5ff 70 }
seajayshore 0:80768ca5d5ff 71
seajayshore 1:1967c3f48465 72 *_adcReading = adcReading;
seajayshore 0:80768ca5d5ff 73
seajayshore 1:1967c3f48465 74 return newReading;
seajayshore 0:80768ca5d5ff 75 }
seajayshore 0:80768ca5d5ff 76
seajayshore 0:80768ca5d5ff 77 // Initialise the HY3116 with the following config.:
seajayshore 0:80768ca5d5ff 78 //
seajayshore 0:80768ca5d5ff 79 void HY3116::init()
seajayshore 0:80768ca5d5ff 80 {
seajayshore 0:80768ca5d5ff 81 // Set the I2C clock frequency
seajayshore 0:80768ca5d5ff 82 i2c.frequency(100000);
seajayshore 0:80768ca5d5ff 83
seajayshore 0:80768ca5d5ff 84 // Set-up the SYS register
seajayshore 0:80768ca5d5ff 85 writeByte(HY3116_ADDRESS, SYS, 0b00011100); // Enable the ADC & LDO
seajayshore 2:2da9fbab02b7 86 wait_ms(1); // wait 100 ms to stabilize
seajayshore 0:80768ca5d5ff 87
seajayshore 0:80768ca5d5ff 88 // Set-up the ADC1 register
seajayshore 0:80768ca5d5ff 89 writeByte(HY3116_ADDRESS, ADC1, 0b00001000); // Set inputs to AIN1 & AIN2
seajayshore 2:2da9fbab02b7 90 wait_ms(1); // wait 100 ms to stabilize
seajayshore 0:80768ca5d5ff 91
seajayshore 0:80768ca5d5ff 92 // Set-up the ADC2 register
seajayshore 0:80768ca5d5ff 93 writeByte(HY3116_ADDRESS, ADC2, 0b01010000); // Set pos. ref. voltage to VDDA, neg. ref. to VSSA, DC offset to 0VRef
seajayshore 2:2da9fbab02b7 94 wait_ms(1); // wait 100 ms to stabilize
seajayshore 0:80768ca5d5ff 95
seajayshore 0:80768ca5d5ff 96 // Set-up the ADC3 register
seajayshore 2:2da9fbab02b7 97 writeByte(HY3116_ADDRESS, ADC3, 0b00111111); // Set to int. osc. 327kHz, full ref. range, PGA to 32x, pre-amp to 2x
seajayshore 2:2da9fbab02b7 98 wait_ms(1); // wait 100 ms to stabilize
seajayshore 0:80768ca5d5ff 99
seajayshore 0:80768ca5d5ff 100 // Set-up the ADC4 register
seajayshore 2:2da9fbab02b7 101 writeByte(HY3116_ADDRESS, ADC4, 0b01001100); // Set LDO to 3.0V, REFO = 1.2V, conv. rate = 327kHz, SPS = 40
seajayshore 2:2da9fbab02b7 102 wait_ms(1); // wait 100 ms to stabilize
seajayshore 0:80768ca5d5ff 103
seajayshore 0:80768ca5d5ff 104 resetChip();
seajayshore 2:2da9fbab02b7 105 wait_ms(1);
seajayshore 0:80768ca5d5ff 106 }