DAC_MCP4922.hpp

00001 //------------------------------------------------------
00002 // Class for single DAC in MCP4922
00003 //
00004 // 2015/04/19, Copyright (c) 2015 MIKAMI, Naoki
00005 //------------------------------------------------------
00006 
00007 #ifndef DAC_MCP4922_HPP
00008 #define DAC_MCP4922_HPP
00009 
00010 #include "DAC_MCP4921.hpp"
00011 
00012 namespace Mikami
00013 {
00014     class DAC_MCP4922 : public DAC_MCP4921
00015     {
00016     public:
00017         enum DAC { DAC_A = 0, DAC_B = 0x8000 };
00018 
00019         // Constructor
00020         DAC_MCP4922(
00021             DAC dac = DAC_A,            // channel A
00022             PinName mosi = SPI_MOSI,    // D11
00023             PinName sclk = SPI_SCK,     // D13
00024             PinName cs   = SPI_CS,      // D10
00025             PinName ldac = SPI_MISO)    // D12
00026                 : DAC_MCP4921(mosi, sclk, cs, ldac),
00027                   wcr_(dac | 0x3000) {}
00028 
00029     protected:
00030         void SetCR(DAC dac) { wcr_ = dac  | 0x3000; }
00031         
00032     private:
00033         uint16_t wcr_;  // write command register
00034 
00035         // for inhibition of copy constructor
00036         DAC_MCP4922(const DAC_MCP4922&);
00037         // for inhibition of substitute operator
00038         DAC_MCP4922& operator=(const DAC_MCP4922&);     
00039         
00040         // for internal use
00041         virtual void WriteDac(uint16_t value)
00042         {
00043             while (IsBusy()) {}
00044             SlaveSelect();
00045             WriteSpi(value | wcr_);
00046         }
00047     };
00048 }
00049 #endif  // DAC_MCP4922_HPP