8-Bit Single/Dual SPI Digital POT with Non-Volatile Memory
Fork of MCP4261 by
MCP4261.cpp
- Committer:
- stjo2809
- Date:
- 2016-01-20
- Revision:
- 2:1e4469bdbed9
- Parent:
- 1:935321af7311
File content as of revision 2:1e4469bdbed9:
/* mbed MCP4261 Library, for driving the 8-Bit Single/Dual SPI Digital POT with Non-Volatile Memory * Copyright (c) 2015, Created by Steen Joergensen (stjo2809) * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "mbed.h" #include "MCP4261.h" //============================================================================= // Public functions //============================================================================= MCP4261::MCP4261(SPI& spi, PinName nCs, PinName nWP, PinName nSHDN): _spi(spi), _nCs(nCs), _nWP(nWP), _nSHDN(nSHDN) { _nCs = 1; } MCP4261::MCP4261(SPI& spi, PinName nCs, PinName nWP): _spi(spi), _nCs(nCs), _nWP(nWP), _nSHDN(NC) { _nCs = 1; } int MCP4261::read(char address) { return _read(address); } void MCP4261::write(char address, int data) { _write(address, data); } void MCP4261::inc(bool number) { if(number == 0) { _make_command_byte(CB_INCR, VW0_ADDR, 0); _nCs = 0; _spi.write(_command_byte); _nCs = 1; } else { _make_command_byte(CB_INCR, VW1_ADDR, 0); _nCs = 0; _spi.write(_command_byte); _nCs = 1; } } void MCP4261::dec(bool number) { if(number == 0) { _make_command_byte(CB_DECR, VW0_ADDR, 0); _nCs = 0; _spi.write(_command_byte); _nCs = 1; } else { _make_command_byte(CB_DECR, VW1_ADDR, 0); _nCs = 0; _spi.write(_command_byte); _nCs = 1; } } int MCP4261::status() { return _read(STATUS_ADDR); } int MCP4261::tcon() { return _read(TCON_ADDR); } void MCP4261::tcon(int data) { _write(TCON_ADDR, data); } int MCP4261::wiper(bool number) { if(number == 0) { return _read(VW0_ADDR); } else { return _read(VW1_ADDR); } } void MCP4261::wiper(bool number, int data) { if(number == 0) { _write(VW0_ADDR, data); } else { _write(VW1_ADDR, data); } } int MCP4261::nvwiper(bool number) { if(number == 0) { return _read(NVW0_ADDR); } else { return _read(NVW1_ADDR); } } void MCP4261::nvwiper(bool number, int data) { if(number == 0) { _write(NVW0_ADDR, data); } else { _write(NVW1_ADDR, data); } } void MCP4261::shdn(bool act) { _nSHDN = ~act; } void MCP4261::wp(bool act) { _nWP = ~act; } //============================================================================= // Private functions //============================================================================= char MCP4261::_make_command_byte(int com, char address, int data) { if(data > 0xff && data <= 0x3FF) { _command_byte = address << 4; // add address to _command_byte _command_byte = _command_byte | (data >> 8); // add data to _command_byte _command_byte = _command_byte | (com << 2); // add com to _command_byte } else { _command_byte = address << 4; // add address to _command_byte _command_byte = _command_byte | (com << 2); // add com to _command_byte } return _command_byte; } int MCP4261::_read(char address) { int _response_msb; int _response_lsb; int _response; _response = 0; // clear _response for old data _response_msb = 0; // clear _response_msb for old data _response_lsb = 0; // clear _response_lsb for old data _make_command_byte(CB_READ, address, 0); _nCs = 0; _response_msb = _spi.write(_command_byte); _response_lsb = _spi.write(0xff); // not important bit of the 16 bits _nCs = 1; _response = _response_msb << 8; _response = _response | _response_lsb; return _response; } void MCP4261::_write(char address, int data) { _make_command_byte(CB_WRITE, address, data); int _send_data = data & 0xff; _nCs = 0; _spi.write(_command_byte); _spi.write(_send_data); _nCs = 1; }