Diff: F446_ADC.cpp

Revision:

4:03e91e464ce5

Parent:

2:29f9831ce719

--- a/F446_ADC.cpp	Mon Jan 30 08:12:44 2017 +0000
+++ b/F446_ADC.cpp	Sun Feb 05 07:59:14 2017 +0000
@@ -9,6 +9,14 @@
 //
 //  2016/11/12, Copyright (c) 2016 MIKAMI, Naoki
 //----------------------------------------------------------
+/*
+ *  Modified by Kenji Arai
+ *      http://www.page.sannet.ne.jp/kenjia/index.html
+ *      http://mbed.org/users/kenjiArai/
+ *
+ *      Started:  Feburary  1st, 2017
+ *      Revised:  Feburary  1st, 2017
+ */
 
 #include "F446_ADC.hpp"
 
@@ -89,4 +97,73 @@
         myTim->PSC = psc;           // Prescaler
         myTim->CR1 = TIM_CR1_CEN;   // Enable TIM8
     }
+
+//------------------------------------------------------------------------------
+
+    AdcSingle::AdcSingle(int frequency)
+    {
+        // ADC input is assigned PA0
+        __HAL_RCC_GPIOA_CLK_ENABLE();
+        GPIO_InitTypeDef gpioInit;
+        gpioInit.Pin = GPIO_PIN_0;
+        gpioInit.Mode = GPIO_MODE_ANALOG;
+        gpioInit.Pull = GPIO_NOPULL;
+        gpioInit.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
+        HAL_GPIO_Init(GPIOA, &gpioInit);
+
+        // ADC2 (port:PA0)
+        __HAL_RCC_ADC2_CLK_ENABLE();
+        ADC2->CR1 = 0x0;
+        ADC2->CR2 = ADC_EXTERNALTRIGCONVEDGE_RISING // Ext. trigger + rising eggde
+                  | ADC_EXTERNALTRIGCONV_T8_TRGO    // Ext. trigger Timer8 TRGO event
+                  | ADC_CR2_ADON;                   // ADC を有効にする
+        ADC2->SQR3 = 0x0;                           // CH0 を使う
+        
+        // ADC 共通の設定
+        ADC->CCR = 0x0;     // 念のため
+
+        // AD 変換器の外部トリガに使うタイマ (TIM8) の設定
+        SetTim8(frequency);
+    }
+
+    void AdcSingle::Read(float &ad)
+    {
+        WaitDone();
+        ad = ToFloat(ADC2->DR);
+    }
+
+    void AdcSingle::Read(uint16_t &ad)
+    {
+        WaitDone();
+        ad = ADC2->DR;
+    }
+
+    void AdcSingle::SetTim8(int frequency)
+    {
+        __HAL_RCC_TIM8_CLK_ENABLE();    // Supply clock. See "stm32f4xx_hal_rcc.h"
+        SystemCoreClockUpdate();        // Update core clock. See "system_stm32f4xx.h"
+        TIM_TypeDef* const myTim = TIM8;
+
+        myTim->CR2 = TIM_CR2_MMS_1; // Update event: as trigger out
+
+    	uint32_t psc = 0;
+        uint16_t mul = 1;
+        uint32_t arr;
+        while (true)
+        {
+            arr = SystemCoreClock/(mul*frequency);
+            if (arr <= 65536) break;
+            psc++;
+            mul++;
+            if (psc > 65535)
+            {
+                fprintf(stderr, "Sampling frequency: too low.\r\n");
+                while (true) {}
+            }
+        }
+        myTim->ARR = arr - 1;       // Auto-reload
+        myTim->PSC = psc;           // Prescaler
+        myTim->CR1 = TIM_CR1_CEN;   // Enable TIM8
+    }
 }
+