Library for Akizuki MCP3425 ADC module
Fork of MCP3425 by
Library for MCP3425 ADC module from Akizuki-denshi.
MCP3425.cpp
- Committer:
- sakurahilljp
- Date:
- 2016-04-15
- Revision:
- 3:378672292488
- Parent:
- 2:7375e645e806
File content as of revision 3:378672292488:
//********************** // MCP3425.cpp for mbed // // (C)Copyright 2016 Satoshi Nihonyanagi, All Rights Reserved. // // (C)Copyright 2014 All rights reserved by Y.Onodera // http://einstlab.web.fc2.com //********************** #include "mbed.h" #include "MCP3425.h" const int MCP3425::ADDR = 0xD0; const float MCP3425::VREF = 2.048; MCP3425::MCP3425(I2C& i2c) : _i2c(i2c), _addr(ADDR) { _init(); } MCP3425::MCP3425(I2C& i2c, int addr) : _i2c(i2c), _addr(addr) { _init(); } void MCP3425::set(MCP3425::Gain gain) { _cfg.bit.G = (unsigned char)gain; _write_cfg(); } void MCP3425::set(MCP3425::Resolution resolution) { _cfg.bit.S = (unsigned char)resolution; _write_cfg(); } void MCP3425::set(MCP3425::Conversion conversion) { _cfg.bit.OC = (unsigned char)conversion; _write_cfg(); } short MCP3425::get() { return _get_code(); } float MCP3425::read() { return _c2v(_get_code()); } void MCP3425::_init() { _cfg.bit.G = (unsigned char)G1; _cfg.bit.S = (unsigned char)W16; _cfg.bit.OC = (unsigned char)ONESHOT; _cfg.bit.C = 0; _cfg.bit.RDY = 0; _write_cfg(); } void MCP3425::_write_cfg() { _buf[0] = _cfg.UC; _i2c.write(_addr, _buf, 1); } short MCP3425::_get_code() { // Trigger updating value if one-shot Mode if (_cfg.bit.OC == 0) { _cfg.bit.RDY = 1; _write_cfg(); } while(1) { if( _i2c.read( ADDR, _buf, 3) != 0 ) { // failed to read (nack) return 0; } _val.byte.HB = _buf[0]; _val.byte.LB = _buf[1]; _cfg.UC = _buf[2]; if(_cfg.bit.RDY == 0 ) break; wait_ms(5); // fastest rate: 240 SPS with 12-bit } return _val.S; } float MCP3425::_c2v(short code) { int gain = 1; if (_cfg.bit.G == 0) gain = 1; else if (_cfg.bit.G == 1) gain = 2; else if (_cfg.bit.G == 2) gain = 4; else if (_cfg.bit.G == 3) gain = 8; int maxcode = 2047; if (_cfg.bit.S == 0 ) maxcode = 2047; else if (_cfg.bit.S == 1 ) maxcode = 8191; else if (_cfg.bit.S == 2 ) maxcode = 32767; return code * VREF / gain / ( maxcode + 1 ); }