不韋 呂
Prototype program of AD and DA using classes in UIT_ADDA. This program uses interrupt of ADC. Second channnel input is used to control volume of output for ST Nucleo F401RE. UIT_ADDA のクラスを使った AD および DA のためのプログラムの雛形．ADC の割り込みを使うバージョン．2番目のチャンネルの ADC の入力は，出力信号の大きさをコントロールするために使う．ST Nucleo F401 用．
Dependencies: UIT_ACM1602NI UIT_ADDA mbed
Diff: main.cpp
- Revision:
- 0:494ae18d3b30
- Child:
- 1:43a38eaed0fc
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Mon Oct 20 07:48:40 2014 +0000
@@ -0,0 +1,56 @@
+//--------------------------------------------------------------
+// 割り込みを使って AD DA を行う場合の雛形2
+// Analog Input : A0
+// Analog Output: MCP4922 using SPI
+// 2014/10/20, Copyright (c) 2014 MIKAMI, Naoki
+//--------------------------------------------------------------
+
+#include "mbed.h"
+
+#include "ADC_Interrupt.hpp" // for ADC using interrupt
+#include "DAC_MCP4922.hpp" // for DAC MCP4922
+#include "ScfClockTim3.hpp" // for clock supplied to SCF
+
+using namespace Mikami;
+
+const int FS_ = 10000; // Sampling frequency: 24 kHz
+ADC_Intr adc_(A0, FS_, A1, A2); // for AD
+DAC_MCP4922 myDac_(DAC_MCP4922::DAC_A); // for DA
+
+uint16_t a2_ = 0;
+uint16_t a21_ = 0;
+float vol_ = 1.0f;
+
+// Interrupt service routine for ADC
+void AdcIsr()
+{
+ float xn = adc_.Read(); // Read from A0
+
+ adc_.Select3rdChannel(); // Enable A2
+ adc_.SoftStart(); // ADC start for A2 input
+
+ float yn = vol_*xn; // Volume control by VR
+ myDac_.Write(yn); // to DAC
+
+ // Read value which controls volume
+ a2_ = adc_.ReadWait_u16();
+
+ adc_.Select1stChannel(); // Enable A0
+ adc_.ClearPending_EnableIRQ(); // Clear pending interrupt
+}
+
+int main()
+{
+ ScfClockTim3(420000); // cutoff frequency: 4.2 kHz
+ adc_.SetIntrVec(AdcIsr); // Assign ISR for ADC interrupt
+
+ while (true)
+ {
+ if (abs(a2_ - a21_) > 10)
+ {
+ vol_ = ((float)a2_)/4095.0f;
+ a21_ = a2_;
+ }
+ wait(0.1f);
+ }
+}