Diff: main.cpp

Revision:

0:1883d922ada8

Child:

1:9913e3886643

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Oct 21 15:23:36 2015 +0000
@@ -0,0 +1,43 @@
+#include "mbed.h"
+#include "HIDScope.h"
+#include "biquadFilter.h"        // Require the HIDScope library
+
+//Define objects
+AnalogIn    emg(A0); //Analog of EMG input
+Ticker      sample_timer;
+HIDScope    scope(2);        // Instantize a 2-channel HIDScope object
+/*The biquad filters required to transform the EMG signal into an usable signal*/
+biquadFilter filterhigh1(-1.1430, 0.4128, 0.6389, -1.2779, 0.6389);
+biquadFilter filterlow1(1.9556, 0.9565, 0.9780, 1.9561, 0.9780);
+biquadFilter notch(-1.1978e-16, 0.9561, 0.9780, -1.1978e-16, 0.9780);
+biquadFilter filterlow2(-1.9645, 0.9651, 1.5515e-4, 3.1030e-4, 1.5515e-4);
+
+/* 
+ */
+void filter()
+{
+    /* Sample the EMG using the 'read' method of the 'AnalogIn' variable named 'emg' */
+    double emg_value = emg.read();
+        double signalpart1 = filterhigh1.step(emg_value);//Highpass filter for removing offset and artifacts
+        double signalpart2 = abs(signalpart1);//rectify the filtered signal
+        double signalpart3 = filterlow1.step(signalpart2);//low pass filter to envelope the emg
+        double signalpart4 = notch.step(signalpart3);//notch filter to remove 50Hz signal
+        double signalfinal = filterlow2.step(signalpart4);//2nd low pass filter to envelope the emg
+        scope.set(0,emg_value);//emg_value
+        scope.set(1,signalfinal);
+        /* Second, set the sampled emg value in channel zero (the first channel) in the 'HIDScope' variable named 'scope' */
+    /* Repeat the step above if required for more channels (channel 0 up to 5 = 6 channels) */
+    /* Finally, send all channels to the PC at once */
+    scope.send();
+}
+
+int main()
+{
+    /**Attach the 'sample' function to the timer 'sample_timer'.
+    * this ensures that 'sample' is executed every... 0.002 seconds
+    */
+    sample_timer.attach(&filter, 0.002);
+
+    /*empty loop, sample() is executed periodically*/
+    while(1) {}
+}
\ No newline at end of file