Class library for internal ADC and DAC connected by SPI. ADC is triggered by TIM2. This library support clock generator using TIM3 for switched-capacitor filter to smooth output signal of DAC. This library includes derivative class to support interrupt occured in end of AD conversion. Slave select of SPI for DAC is generated using TIM4. Validated for ST Nucleo F401RE, F411RE. New version. 内蔵 ADC と,SPI 接続の DAC のためのクラスライブラリ.ADC の変換開始トリガは TIM2 で発生.DAC の出力信号を平滑化するためのスイッチトキャパシタフィルタ用のクロックは TIM3 を使用.DAC の SPI 用スレーブ選択信号は TIM4 で発生.ST Nucleo F401RE,F411RE で動作を確認.新バージョン

Dependents:   UIT2_MovingAverage UIT2_AllpassReverb UIT2_CombReverb UIT2_FIR_LPF_Symmetry ... more

Revision:
20:c49f3b565a87
Parent:
19:900efc6796d4
Child:
21:3731753ebf24
diff -r 900efc6796d4 -r c49f3b565a87 DAC_MCP4922.hpp
--- a/DAC_MCP4922.hpp	Fri Jan 30 07:22:28 2015 +0000
+++ b/DAC_MCP4922.hpp	Mon Feb 02 08:10:55 2015 +0000
@@ -2,32 +2,17 @@
 // Class for single DAC in MCP4922 -- Header
 //      Fast version
 //
-// Default pin assign
-//      D11  SPI Master Out Slave In
-//      D13  SPI Serial Clock
-//      D10  SPI Slave Select ----------------------- TIM4
-//      D12  to MCP4922 LDAC pin
-//      D9   clock for Switched-capacitor filter ---- TIM3
-//
-// Argument cs in constructor must be output of TIM4,
-// i.e. D10(PB_6), PB_7, D15(PB_8), or D14(PB_9)
-//
-// Argument pin in function ScfClockTim3() can be
-// PA_6(D12), PB_4(D5), PC_6, PB_5(D4), PC_7(D9),
-// PC_8, or PC_9
-//
-// 2015/01/30, Copyright (c) 2014 MIKAMI, Naoki
+// 2015/02/02, Copyright (c) 2015 MIKAMI, Naoki
 //------------------------------------------------------
 
 #ifndef DAC_MCP4922_HPP
 #define DAC_MCP4922_HPP
 
-#include "mbed.h"
-#include "tim4_slaveSelect.hpp"
+#include "DAC_MCP4921.hpp"
 
 namespace Mikami
 {
-    class DAC_MCP4922
+    class DAC_MCP4922 : public DAC_MCP4921
     {
     public:
         enum DAC { DAC_A = 0, DAC_B = 0x8000 };
@@ -38,48 +23,12 @@
             PinName mosi = SPI_MOSI,    // D11
             PinName sclk = SPI_SCK,     // D13
             PinName cs   = SPI_CS,      // D10
-            PinName ldac = SPI_MISO);   // D12
-
-        // -1.0f <= value <= 1.0f
-        void Write(float value)
-        {
-            if (value < -1.0f) value = -1.0f;
-            if (value >  1.0f) value =  1.0f;
-
-            WriteDac((uint16_t)((value + 1.0f)*2047));
-        }
-
-        // 0 <= value <= 4095
-        void Write(uint16_t value)
-        {   WriteDac((value > 4095) ? 4095 : value); }
-        
-        // generate LDAC negative-going pulse
-        void Ldac()
-        {
-            ld_.write(0);
-            ld_.write(0);   // ensure width of "L" pulse
-            ld_.write(1);
-        }
-
-        // Check busy
-        bool IsBusy()
-        {   return (mySpi_->SR & SPI_SR_BSY) == SPI_SR_BSY; }
-        
-        // Little wait
-        void Wait()
-        {   __NOP(); __NOP(); __NOP(); }
-            
-        // Set clock for switched-capacitor filter
-        void ScfClockTim3(uint32_t clock, PinName pin = D9);
+            PinName ldac = SPI_MISO)    // D12
+                : DAC_MCP4921(mosi, sclk, cs, ldac),
+                  wcr_(dac | 0x3000) {}
 
     private:
         uint16_t wcr_;  // write command register
-        SPI spi_;       // SPI object of mbed
-        Tim4_ss* ss_;
-        DigitalOut ld_; // for LDAC
-
-        // Pointer of I2C
-        SPI_TypeDef* mySpi_;
 
         // for inhibition of copy constructor
         DAC_MCP4922(const DAC_MCP4922&);
@@ -87,13 +36,12 @@
         DAC_MCP4922& operator=(const DAC_MCP4922&);     
         
         // for internal use
-        void WriteDac(uint16_t value)
+        virtual void WriteDac(uint16_t value)
         {
             while (IsBusy()) {}
-            ss_->SlaveSelect();
-            mySpi_->DR = value | wcr_;
+            SlaveSelect();
+            WriteSpi(value | wcr_);
         }
     };
 }
 #endif  // DAC_MCP4922_HPP
-