Satoshi Nihonyanagi / MCP3425AK

Library for Akizuki MCP3425 ADC module

Fork of MCP3425 by yasuyuki onodera

Library for MCP3425 ADC module from Akizuki-denshi.

MCP3425.cpp@2:7375e645e806, 2016-04-13 (annotated)

Committer:
sakurahilljp
Date:
Wed Apr 13 14:45:11 2016 +0000
Revision:
2:7375e645e806
Parent:
1:5ac344aa0aac
Child:
3:378672292488
Added to methods to  specify gain, resolution and conversion operation mode.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
yasuyuki 0:b7bc51be525f 1 //**********************
yasuyuki 0:b7bc51be525f 2 // MCP3425.cpp for mbed
yasuyuki 0:b7bc51be525f 3 //
yasuyuki 0:b7bc51be525f 4 // MCP3425 mcp3425(P0_5,P0_4);
yasuyuki 0:b7bc51be525f 5 // or
yasuyuki 0:b7bc51be525f 6 // I2C i2c(P0_5,P0_4);
yasuyuki 0:b7bc51be525f 7 // MCP3425 mcp3425(i2c);
yasuyuki 0:b7bc51be525f 8 //
yasuyuki 0:b7bc51be525f 9 // (C)Copyright 2014 All rights reserved by Y.Onodera
yasuyuki 0:b7bc51be525f 10 // http://einstlab.web.fc2.com
yasuyuki 0:b7bc51be525f 11 //**********************
yasuyuki 0:b7bc51be525f 12
yasuyuki 0:b7bc51be525f 13 #include "mbed.h"
yasuyuki 0:b7bc51be525f 14 #include "MCP3425.h"
yasuyuki 0:b7bc51be525f 15
sakurahilljp 2:7375e645e806 16 const int MCP3425::ADDR = 0xD0;
sakurahilljp 1:5ac344aa0aac 17 const float MCP3425::VREF = 2.048;
sakurahilljp 1:5ac344aa0aac 18
sakurahilljp 2:7375e645e806 19
sakurahilljp 2:7375e645e806 20 MCP3425::MCP3425(I2C& i2c)
sakurahilljp 2:7375e645e806 21 : _i2c(i2c), _addr(ADDR)
sakurahilljp 2:7375e645e806 22 {
sakurahilljp 2:7375e645e806 23 _init();
yasuyuki 0:b7bc51be525f 24 }
sakurahilljp 2:7375e645e806 25
sakurahilljp 2:7375e645e806 26 MCP3425::MCP3425(I2C& i2c, int addr)
sakurahilljp 2:7375e645e806 27 : _i2c(i2c), _addr(addr)
sakurahilljp 2:7375e645e806 28 {
sakurahilljp 2:7375e645e806 29 _init();
yasuyuki 0:b7bc51be525f 30 }
yasuyuki 0:b7bc51be525f 31
sakurahilljp 2:7375e645e806 32 void MCP3425::set(MCP3425::Gain gain)
sakurahilljp 2:7375e645e806 33 {
sakurahilljp 2:7375e645e806 34 _cfg.bit.G = (unsigned char)gain;
sakurahilljp 2:7375e645e806 35 _write_cfg();
sakurahilljp 2:7375e645e806 36 }
sakurahilljp 2:7375e645e806 37
sakurahilljp 2:7375e645e806 38 void MCP3425::set(MCP3425::Resolution resolution)
sakurahilljp 2:7375e645e806 39 {
sakurahilljp 2:7375e645e806 40 _cfg.bit.S = (unsigned char)resolution;
sakurahilljp 2:7375e645e806 41 _write_cfg();
sakurahilljp 2:7375e645e806 42 }
sakurahilljp 2:7375e645e806 43
sakurahilljp 2:7375e645e806 44 void MCP3425::set(MCP3425::Conversion conversion)
sakurahilljp 2:7375e645e806 45 {
sakurahilljp 2:7375e645e806 46 _cfg.bit.OC = (unsigned char)conversion;
sakurahilljp 2:7375e645e806 47 _write_cfg();
sakurahilljp 2:7375e645e806 48 }
yasuyuki 0:b7bc51be525f 49
yasuyuki 0:b7bc51be525f 50 short MCP3425::get()
yasuyuki 0:b7bc51be525f 51 {
sakurahilljp 2:7375e645e806 52 return _get_code();
sakurahilljp 1:5ac344aa0aac 53 }
sakurahilljp 1:5ac344aa0aac 54
sakurahilljp 1:5ac344aa0aac 55 float MCP3425::read()
sakurahilljp 1:5ac344aa0aac 56 {
sakurahilljp 2:7375e645e806 57 short code = get();
sakurahilljp 2:7375e645e806 58
sakurahilljp 1:5ac344aa0aac 59 int gain = 1;
sakurahilljp 2:7375e645e806 60 if (_cfg.bit.G == 0) gain = 1;
sakurahilljp 2:7375e645e806 61 else if (_cfg.bit.G == 1) gain = 2;
sakurahilljp 2:7375e645e806 62 else if (_cfg.bit.G == 2) gain = 4;
sakurahilljp 2:7375e645e806 63 else if (_cfg.bit.G == 3) gain = 8;
sakurahilljp 1:5ac344aa0aac 64
sakurahilljp 1:5ac344aa0aac 65 int maxcode = 2047;
sakurahilljp 2:7375e645e806 66 if (_cfg.bit.S == 0 ) maxcode = 2047;
sakurahilljp 2:7375e645e806 67 else if (_cfg.bit.S == 1 ) maxcode = 8191;
sakurahilljp 2:7375e645e806 68 else if (_cfg.bit.S == 2 ) maxcode = 32767;
sakurahilljp 2:7375e645e806 69
sakurahilljp 2:7375e645e806 70 return code * VREF / gain / ( maxcode + 1 );
sakurahilljp 2:7375e645e806 71 }
sakurahilljp 2:7375e645e806 72
sakurahilljp 2:7375e645e806 73 void MCP3425::_init()
sakurahilljp 2:7375e645e806 74 {
sakurahilljp 2:7375e645e806 75 _cfg.bit.G = (unsigned char)G1;
sakurahilljp 2:7375e645e806 76 _cfg.bit.S = (unsigned char)W16;
sakurahilljp 2:7375e645e806 77 _cfg.bit.OC = (unsigned char)ONESHOT;
sakurahilljp 2:7375e645e806 78 _cfg.bit.C = 0;
sakurahilljp 2:7375e645e806 79 _cfg.bit.RDY = 0;
sakurahilljp 2:7375e645e806 80
sakurahilljp 2:7375e645e806 81 _write_cfg();
yasuyuki 0:b7bc51be525f 82 }
yasuyuki 0:b7bc51be525f 83
sakurahilljp 2:7375e645e806 84 void MCP3425::_write_cfg()
yasuyuki 0:b7bc51be525f 85 {
sakurahilljp 2:7375e645e806 86 _buf[0] = _cfg.UC;
sakurahilljp 2:7375e645e806 87 _i2c.write(_addr, _buf, 1);
yasuyuki 0:b7bc51be525f 88 }
yasuyuki 0:b7bc51be525f 89
sakurahilljp 2:7375e645e806 90 short MCP3425::_get_code()
sakurahilljp 2:7375e645e806 91 {
sakurahilljp 2:7375e645e806 92 // Trigger updating value if one-shot Mode
sakurahilljp 2:7375e645e806 93 if (_cfg.bit.OC == 0)
sakurahilljp 2:7375e645e806 94 {
sakurahilljp 2:7375e645e806 95 _cfg.bit.RDY = 1;
sakurahilljp 2:7375e645e806 96 _write_cfg();
sakurahilljp 2:7375e645e806 97 }
sakurahilljp 2:7375e645e806 98
sakurahilljp 2:7375e645e806 99 while(1) {
sakurahilljp 2:7375e645e806 100 if( _i2c.read( ADDR, _buf, 3) != 0 )
sakurahilljp 2:7375e645e806 101 {
sakurahilljp 2:7375e645e806 102 // failed to read (nack)
sakurahilljp 2:7375e645e806 103 return 0;
sakurahilljp 2:7375e645e806 104 }
sakurahilljp 2:7375e645e806 105
sakurahilljp 2:7375e645e806 106 _val.byte.HB = _buf[0];
sakurahilljp 2:7375e645e806 107 _val.byte.LB = _buf[1];
sakurahilljp 2:7375e645e806 108 _cfg.UC = _buf[2];
sakurahilljp 2:7375e645e806 109
sakurahilljp 2:7375e645e806 110 if(_cfg.bit.RDY == 0 ) break;
sakurahilljp 2:7375e645e806 111 wait_ms(5); // fastest rate: 240 SPS with 12-bit
sakurahilljp 2:7375e645e806 112 }
sakurahilljp 2:7375e645e806 113
sakurahilljp 2:7375e645e806 114 return _val.S;
sakurahilljp 2:7375e645e806 115 }