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@0:74353da3eacd, 2013-02-13 (annotated)

Committer:
NickRyder
Date:
Wed Feb 13 16:08:13 2013 +0000
Revision:
0:74353da3eacd
Child:
1:68b3a24fd2a4
Added documentation.

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 0:74353da3eacd 6 //! MCP4822 dual 12-bit DAC
NickRyder 0:74353da3eacd 7 class MCP4822 {
NickRyder 0:74353da3eacd 8 public:
NickRyder 0:74353da3eacd 9 /** Create an MCP4822 instance
NickRyder 0:74353da3eacd 10 * @param dataout SPI MOSI pin (should be p5 or p11)
NickRyder 0:74353da3eacd 11 * @param clock SPI clock pin (should be p7 or p13)
NickRyder 0:74353da3eacd 12 * @param chipselect SPI chip select pin (can be any)
NickRyder 0:74353da3eacd 13 * @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 14 */
NickRyder 0:74353da3eacd 15 MCP4822(PinName dataout, PinName clock, PinName chipselect, PinName latch);
NickRyder 0:74353da3eacd 16 //! Set output A to voltage
NickRyder 0:74353da3eacd 17 void setA(float voltage);
NickRyder 0:74353da3eacd 18 //! Set output B to voltage
NickRyder 0:74353da3eacd 19 void setB(float voltage);
NickRyder 0:74353da3eacd 20 //! Set both output A to voltageA and outputB to voltageB
NickRyder 0:74353da3eacd 21 void set(float voltageA, float voltageB);
NickRyder 0:74353da3eacd 22 //! Latch the stored values to the output pins
NickRyder 0:74353da3eacd 23 void latch();
NickRyder 0:74353da3eacd 24 //! shut down output from the DAC chip
NickRyder 0:74353da3eacd 25 void shutdown();
NickRyder 0:74353da3eacd 26 private:
NickRyder 0:74353da3eacd 27 DigitalOut cs, latchpin;
NickRyder 0:74353da3eacd 28 SPI spi;
NickRyder 0:74353da3eacd 29 void write(bool chanB, bool gain1, unsigned int voltage, bool shutdown = false);
NickRyder 0:74353da3eacd 30 void setvoltage(float voltage, bool chanB = false);
NickRyder 0:74353da3eacd 31 };
NickRyder 0:74353da3eacd 32
NickRyder 0:74353da3eacd 33
NickRyder 0:74353da3eacd 34 #endif