Nick Ryder / MCP4822lib

MCP4822 dual 12-bit Digital to Analog Converter (DAC) chip.

Dependents:   ADC2DAC

The MCP4822 is a dual 12-bit Digital to Analog Converter that is controlled via an SPI interface. It is available in PDIP, SOIC or MSOP packages. The documentation for the chip is available at Microchip's MC4822 page.

The range also includes 8 or 10-bit DACs, which this library could easily be converted to.

MCP4822.h@3:7484c0fe6f4d, 2013-03-04 (annotated)

Committer:
atyeomans
Date:
Mon Mar 04 17:06:01 2013 +0000
Revision:
3:7484c0fe6f4d
Parent:
2:e60995ceccbd 
Added individual shutdowns

Who changed what in which revision?

UserRevisionLine numberNew contents of line
NickRyder 0:74353da3eacd 1 #ifndef __MCP4822_H__
NickRyder 0:74353da3eacd 2 #define __MCP4822_H__
NickRyder 0:74353da3eacd 3
NickRyder 0:74353da3eacd 4 #include "mbed.h"
NickRyder 0:74353da3eacd 5
NickRyder 1:68b3a24fd2a4 6 /** MCP4822 dual 12-bit DAC
NickRyder 1:68b3a24fd2a4 7 * @author NickRyder, atyeomans
NickRyder 2:e60995ceccbd 8 * @version 1.1
NickRyder 1:68b3a24fd2a4 9 * @section LICENSE
NickRyder 1:68b3a24fd2a4 10 * The MIT License (MIT)
NickRyder 1:68b3a24fd2a4 11 * Copyright (c) 2013 Nick Ryder, Andrew Yeomans
NickRyder 1:68b3a24fd2a4 12 *
NickRyder 1:68b3a24fd2a4 13 * Permission is hereby granted, free of charge, to any person obtaining a copy
NickRyder 1:68b3a24fd2a4 14 * of this software and associated documentation files (the "Software"), to deal
NickRyder 1:68b3a24fd2a4 15 * in the Software without restriction, including without limitation the rights
NickRyder 1:68b3a24fd2a4 16 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
NickRyder 1:68b3a24fd2a4 17 * of the Software, and to permit persons to whom the Software is furnished to do so,
NickRyder 1:68b3a24fd2a4 18 * subject to the following conditions:
NickRyder 1:68b3a24fd2a4 19 *
NickRyder 1:68b3a24fd2a4 20 * The above copyright notice and this permission notice shall be included in all
NickRyder 1:68b3a24fd2a4 21 * copies or substantial portions of the Software.
NickRyder 1:68b3a24fd2a4 22 *
NickRyder 1:68b3a24fd2a4 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
NickRyder 1:68b3a24fd2a4 24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
NickRyder 1:68b3a24fd2a4 25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
NickRyder 1:68b3a24fd2a4 26 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
NickRyder 1:68b3a24fd2a4 27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
NickRyder 1:68b3a24fd2a4 28 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
NickRyder 1:68b3a24fd2a4 29 */
NickRyder 1:68b3a24fd2a4 30
NickRyder 0:74353da3eacd 31 class MCP4822 {
NickRyder 0:74353da3eacd 32 public:
NickRyder 0:74353da3eacd 33 /** Create an MCP4822 instance
NickRyder 0:74353da3eacd 34 * @param dataout SPI MOSI pin (should be p5 or p11)
NickRyder 0:74353da3eacd 35 * @param clock SPI clock pin (should be p7 or p13)
NickRyder 0:74353da3eacd 36 * @param chipselect SPI chip select pin (can be any)
NickRyder 0:74353da3eacd 37 * @param latch Latch pin updates the DAC out. Can be any pin or NC, if NC then the latch pin on the DAC chip should be held to GND.
NickRyder 0:74353da3eacd 38 */
NickRyder 0:74353da3eacd 39 MCP4822(PinName dataout, PinName clock, PinName chipselect, PinName latch);
NickRyder 0:74353da3eacd 40 //! Set output A to voltage
NickRyder 0:74353da3eacd 41 void setA(float voltage);
NickRyder 0:74353da3eacd 42 //! Set output B to voltage
NickRyder 0:74353da3eacd 43 void setB(float voltage);
NickRyder 0:74353da3eacd 44 //! Set both output A to voltageA and outputB to voltageB
NickRyder 0:74353da3eacd 45 void set(float voltageA, float voltageB);
NickRyder 0:74353da3eacd 46 //! Latch the stored values to the output pins
NickRyder 0:74353da3eacd 47 void latch();
NickRyder 0:74353da3eacd 48 //! shut down output from the DAC chip
NickRyder 0:74353da3eacd 49 void shutdown();
NickRyder 2:e60995ceccbd 50 //! shut down output form channel A
NickRyder 2:e60995ceccbd 51 void shutdownA();
NickRyder 2:e60995ceccbd 52 //! shut down output form channel B
NickRyder 2:e60995ceccbd 53 void shutdownB();
atyeomans 3:7484c0fe6f4d 54 //! Toggle chip select pin
atyeomans 3:7484c0fe6f4d 55 void chipSel();
NickRyder 0:74353da3eacd 56 private:
NickRyder 0:74353da3eacd 57 DigitalOut cs, latchpin;
NickRyder 0:74353da3eacd 58 SPI spi;
NickRyder 0:74353da3eacd 59 void write(bool chanB, bool gain1, unsigned int voltage, bool shutdown = false);
NickRyder 0:74353da3eacd 60 void setvoltage(float voltage, bool chanB = false);
NickRyder 0:74353da3eacd 61 };
NickRyder 0:74353da3eacd 62
NickRyder 0:74353da3eacd 63
NickRyder 0:74353da3eacd 64 #endif