added direct setting of accel offsets

git-svn-id: https://arducopter.googlecode.com/svn/trunk@1160 f9c3cf11-9bcb-44bc-f272-b75c42450872

libraries/AP_IMU/AP_IMU.cpp

@@ -224,10 +224,12 @@ AP_IMU::get_accel(void)
 	for (int i = 3; i < 6; i++) {
 		_adc_in[i] = _adc->Ch(_sensors[i]);
 		_adc_in[i] -= 2025;								// Subtract typical accel bias
+
 		if (_sensor_signs[i] < 0)
-			_adc_in[i] = (_adc_offset[i] - _adc_in[i]);
+			_adc_in[i] = _adc_offset[i] - _adc_in[i];
 		else
-			_adc_in[i] = (_adc_in[i] - _adc_offset[i]);		
+			_adc_in[i] = _adc_in[i] - _adc_offset[i];
+			
 		if (fabs(_adc_in[i]) > ADC_CONSTRAINT) {
 			adc_constraints++; 												// We keep track of the number of times		
 			_adc_in[i] = constrain(_adc_in[i], -ADC_CONSTRAINT, ADC_CONSTRAINT);	// Throw out nonsensical values

libraries/AP_IMU/AP_IMU.h

@@ -31,6 +31,11 @@ public:
 	void		save_accel_eeprom(void);
 	void 		print_accel_offsets(void);
 	void 		print_gyro_offsets(void);
+	
+	void		ax(const int v)		{ _adc_offset[3] = v; }
+	void		ay(const int v)		{ _adc_offset[4] = v; }
+	void		az(const int v)		{ _adc_offset[5] = v; }
+
 
 	// raw ADC values - called by DCM
 	Vector3f	get_gyro(void);									// Radians/second