Diff: F446_DAC.hpp

Revision:

0:c945b4fe9a48

Child:

1:6b9f2af6613d

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/F446_DAC.hpp	Fri Nov 11 06:28:48 2016 +0000
@@ -0,0 +1,77 @@
+//--------------------------------------------------------
+//  Class for buit-in dual DAC on STM32F446 ---- Header
+//      TIM3 is used for clock to external SCF
+//
+//  STM32F446 内蔵の DAC 用のクラス（ヘッダ）
+//      TIM3 を外付けの SCF のクロックとして使用
+//      Analog Out1: A2  (PA_4)
+//      Analog Out2: D13 (PA_5)
+//
+//  2016/11/11, Copyright (c) 2016 MIKAMI, Naoki
+//--------------------------------------------------------
+
+#include "mbed.h"
+
+#ifndef STM32F446xx
+#error Select STM32F446.
+#endif
+
+#ifndef F446_DAC_DUAL_HPP
+#define F446_DAC_DUAL_HPP
+
+namespace Mikami
+{
+    class DacDual
+    {
+    public:
+        // Constructor
+        DacDual() : da1_(PA_4), da2_(PA_5)
+        {
+            DAC->CR = DAC_CR_EN1 | DAC_CR_TEN1 | DAC_CR_TSEL1 |
+                      DAC_CR_EN2 | DAC_CR_TEN2 | DAC_CR_TSEL2;
+        }
+
+        virtual ~DacDual() {}
+
+        // -1.0f <= data1, data2 <= 1.0f
+        void Write(float data1, float data2)
+        {   WriteDac(ToUint16(data2), ToUint16(data1)); }
+
+        // 0 <= data1, data2 <= 4095
+        void Write(uint16_t data1, uint16_t data2)
+        {   WriteDac(SatUint16(data2), SatUint16(data1)); }
+        
+        // Set TIM3 for clock of switched-capacitor filter
+        void ScfClock(uint32_t clock);
+
+    private:
+        static const uint32_t swtrig_ = DAC_SWTRIGR_SWTRIG1
+                                      | DAC_SWTRIGR_SWTRIG2;
+        AnalogOut da1_, da2_;
+
+        // Write dual-channel data
+        void WriteDac(uint16_t val1, uint16_t val2)
+        {
+            DAC->DHR12RD = (val2 << 16) | val1;
+            DAC->SWTRIGR = swtrig_;
+        }
+
+        // Saturate float to an unsigned 16-bit value
+        uint16_t ToUint16(float val)
+        {
+            if (val < -1.0f) val = -1.0f;
+            if (val >  1.0f) val =  1.0f;
+            return (uint16_t)((val + 1.0f)*2047);
+        }
+        
+        // Saturate to an unsigned 16-bit value
+        uint16_t SatUint16(uint16_t val)
+        {   return (val > 4095) ? 4095 : val; }
+
+        // for inhibition of copy constructor
+        DacDual(const DacDual&);
+        // for inhibition of substitute operator
+        DacDual& operator=(const DacDual&);     
+    };
+}
+#endif  // F446_DAC_DUAL_HPP
\ No newline at end of file