Diff: main.cpp

Revision:

19:dbc1bca498e3

Parent:

18:fed07cc1f8f6

Child:

20:f7d281e3112b

--- a/main.cpp	Mon Sep 29 11:42:37 2014 +0000
+++ b/main.cpp	Mon Sep 29 12:01:13 2014 +0000
@@ -6,42 +6,18 @@
 
 //Define objects
 AnalogIn    emg0(PTB1); //Analog input
-PwmOut      red(LED_RED); //PWM output
 Ticker log_timer;
 MODSERIAL pc(USBTX,USBRX);
 HIDScope scope(2);
 
 arm_biquad_casd_df1_inst_f32 lowpass;
+//constants for 5Hz 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;
+//constants for 0.5Hz 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];
-    float a[3];
-} second_order_constants_t;
 
-typedef struct second_order_values
-{
-    float x_1,x_2;
-    float y_1,y_2;
-} second_order_values_t;
-
-//constants
-second_order_constants_t highpass= {{0.97803048, -1.95606096,  0.97803048},{1, -1.95557824,  0.95654368}};
-second_order_constants_t lowpass={{ 0.02008337 , 0.04016673 , 0.02008337},{1.0,         -1.56101808,  0.64135154}};
-//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)
@@ -63,57 +39,36 @@
     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)
     emg_value_f32 = emg0.read();
-    //filtered_emg = second_order((float)emg_value,highpass, highpass_values);
+
+    //process emg
     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,filtered_emg);
+    
+    /*send value to PC. */
+    scope.set(0,emg_value);     //uint value
+    scope.set(1,filtered_emg);  //processed float
     scope.send();
 
-    /**When not using the LED, the above could also have been done this way:
-    * pc.printf("%u\n", emg0.read_u16());
-    */
 }
 
 int main()
 {
-    /*setup baudrate. Choose the same in your program on PC side*/
-    //pc.baud(115200);
-    /*set the period for the PWM to the red LED*/
-    red.period_ms(2);
+
+   //set up filters. Use external array for constants
+    arm_biquad_cascade_df1_init_f32(&lowpass,1 , lowpass_const, lowpass.pState);
+    arm_biquad_cascade_df1_init_f32(&highpass,1 ,highpass_const,highpass.pState);
+
     /**Here you attach the 'void looper(void)' function to the Ticker object
     * 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
     {
       /*Empty!*/
       /*Everything is handled by the interrupt routine now!*/
     }
-}
-
-
-/*
-float second_order(float x, second_order_constants_t constants, second_order_values_t &values)
-{
-    float y = 0;
-    float b_terms, a_terms;
-    b_terms = (constants.b[0]*x) + (constants.b[1]*values.x_1) + (constants.b[2]*values.x_2);
-    a_terms = (constants.a[1]*values.y_1) + (constants.a[2]*values.y_2);
-    y=(1./constants.a[0])* (b_terms-a_terms);
-    values.x_2 = values.x_1;
-    values.x_1 = x;
-    values.y_2 = values.y_1;
-    values.y_1 = y;
-    return y;
-}*/
\ No newline at end of file
+}
\ No newline at end of file