Diff: main.cpp

Revision:

18:fed07cc1f8f6

Parent:

17:1388f1a2d7b2

Child:

19:dbc1bca498e3

--- a/main.cpp	Wed Sep 24 12:21:00 2014 +0000
+++ b/main.cpp	Mon Sep 29 11:42:37 2014 +0000
@@ -2,6 +2,8 @@
 #include "MODSERIAL.h"
 #include "HIDScope.h"
 
+#include "arm_math.h"
+
 //Define objects
 AnalogIn    emg0(PTB1); //Analog input
 PwmOut      red(LED_RED); //PWM output
@@ -9,6 +11,15 @@
 MODSERIAL pc(USBTX,USBRX);
 HIDScope scope(2);
 
+arm_biquad_casd_df1_inst_f32 lowpass;
+float lowpass_const[] = {0.02008337 , 0.04016673 , 0.02008337 , 1.56101808 , -0.64135154};
+float lowpass_states[4];
+
+arm_biquad_casd_df1_inst_f32 highpass;
+float highpass_const[] = {0.97803048, -1.95606096,  0.97803048, 1.95557824 , -0.95654368};
+volatile float highpass_states[4];
+
+/*
 typedef struct second_order_constants
 {
     float b[3];
@@ -27,8 +38,10 @@
 //type for values
 second_order_values_t highpass_values, lowpass_values;
 
+
+//function definition
 float second_order(float x, second_order_constants_t constants, second_order_values_t &values);
-
+*/
 
 /** Looper function
 * functions used for Ticker and Timeout should be of type void <name>(void)
@@ -48,14 +61,19 @@
     /*variable to store value in*/    
     uint16_t emg_value;
     float filtered_emg;
+    float emg_value_f32;
     /*put raw emg value both in red and in emg_value*/
     red.write(emg0.read());      // read float value (0..1 = 0..3.3V)
     emg_value = emg0.read_u16(); // read direct ADC result, converted to 16 bit integer (0..2^16 = 0..65536 = 0..3.3V)
-    filtered_emg = second_order((float)emg_value,highpass, highpass_values);
+    emg_value_f32 = emg0.read();
+    //filtered_emg = second_order((float)emg_value,highpass, highpass_values);
+    arm_biquad_cascade_df1_f32(&highpass, &emg_value_f32, &filtered_emg, 1 );
+    filtered_emg = fabs(filtered_emg);
+    arm_biquad_cascade_df1_f32(&lowpass, &filtered_emg, &filtered_emg, 1 );
     /*send value to PC. Line below is used to prevent buffer overrun */
-
     scope.set(0,emg_value);
-    scope.set(1,second_order(fabs(filtered_emg), lowpass, lowpass_values));
+    //scope.set(1,second_order(fabs(filtered_emg), lowpass, lowpass_values));
+    scope.set(1,filtered_emg);
     scope.send();
 
     /**When not using the LED, the above could also have been done this way:
@@ -73,6 +91,9 @@
     * The looper() function will be called every 0.01 seconds.
     * Please mind that the parentheses after looper are omitted when using attach.
     */
+    //set up filters
+    arm_biquad_cascade_df1_init_f32(&lowpass,1 , lowpass_const, lowpass_states);
+    arm_biquad_cascade_df1_init_f32(&highpass,1 ,highpass_const, (float *)highpass_states);
     log_timer.attach(looper, 0.005);
     while(1) //Loop
     {
@@ -81,6 +102,8 @@
     }
 }
 
+
+/*
 float second_order(float x, second_order_constants_t constants, second_order_values_t &values)
 {
     float y = 0;
@@ -93,4 +116,4 @@
     values.y_2 = values.y_1;
     values.y_1 = y;
     return y;
-}
\ No newline at end of file
+}*/
\ No newline at end of file