basic test to get quaternion over ble and use it to improve balance board skills

Dependencies:   BLE_API eMPL_MPU6050 mbed nRF51822

Fork of Seeed_Tiny_BLE_Get_Started by Seeed

Revision:
0:26da608265f8
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/battery.h	Sat Feb 07 08:13:51 2015 +0000
@@ -0,0 +1,43 @@
+
+
+#ifndef __BATTERY_H__
+#define __BATTERY_H__
+
+#include "mbed.h"
+
+class Battery {
+public:
+    Battery(PinName pin) {
+        uint32_t n = (uint32_t) pin;
+        channel = 1 << (1 + n);
+    }
+    
+    float read() {
+        uint32_t pre_enable_register = NRF_ADC->ENABLE;
+        uint32_t pre_config_register = NRF_ADC->CONFIG;
+        
+        
+        NRF_ADC->ENABLE = ADC_ENABLE_ENABLE_Enabled;
+        NRF_ADC->CONFIG = (ADC_CONFIG_RES_10bit << ADC_CONFIG_RES_Pos) |
+                          (ADC_CONFIG_INPSEL_AnalogInputNoPrescaling << ADC_CONFIG_INPSEL_Pos) |
+                          (ADC_CONFIG_REFSEL_VBG << ADC_CONFIG_REFSEL_Pos) |
+                          (channel << ADC_CONFIG_PSEL_Pos) |
+                          (ADC_CONFIG_EXTREFSEL_None << ADC_CONFIG_EXTREFSEL_Pos);
+                          
+        NRF_ADC->TASKS_START = 1;
+        while (((NRF_ADC->BUSY & ADC_BUSY_BUSY_Msk) >> ADC_BUSY_BUSY_Pos) == ADC_BUSY_BUSY_Busy) {
+        } 
+        
+        uint16_t value = NRF_ADC->RESULT;
+        
+        NRF_ADC->ENABLE = pre_enable_register;
+        NRF_ADC->CONFIG = pre_config_register;
+        
+        return (float)value * (1.0f / (float)0x3FF) * 1.2 * 12.2 / 2.2;    
+    }
+    
+private:
+    uint32_t channel;
+};
+
+#endif // __BATTERY_H__