APP_Framework/Framework/: complete one order RC high pass filter.

APP_Framework/Framework/knowing/filter/high_pass_filter/one_order_rc_hpf.c

@@ -1 +1,22 @@
-#include<one_order_rc_hpf.h>
+#include<one_order_rc_hpf.h>
+void OneOrderRcHpfInit(OneOrderRcHpfHander* hander,float cutoff_fre,float sampling)
+{
+    hander->vi = 0;
+    hander->fcutoff = cutoff_fre;   // low pass filter cutoff frequency
+    hander->vo = 0;
+    hander->vo_prev = 0;
+    hander->fs = sampling;          //sampling rate
+    hander->vi_prev = 0;
+}
+
+float OneOrderRcHpfFun(OneOrderRcHpfHander *hander)
+{
+    float rc;
+    float alpha;
+    rc = (float) 1.0/2.0/3.1415926/hander->fcutoff;
+    alpha = rc/(rc+1/hander->fs);
+    hander->vo = (hander->vi - hander->vi_prev + hander->vo_prev)*alpha;
+    hander->vi_prev = hander ->vi;
+    hander->vo_prev = hander ->vo;
+    return hander->vo;
+}

APP_Framework/Framework/knowing/filter/high_pass_filter/one_order_rc_hpf.h

@@ -1,5 +1,17 @@
 #ifndef _ONE_ORDER_RC_HPF_H 
 #define _ONE_ORDER_RC_HPF_H
 
+typedef struct 
+{
+	float  vi;
+	float  vi_prev;
+    float  vo_prev;
+	float  vo;
+	float  fcutoff;
+	float  fs;
+} OneOrderRcHpfHander;
+
+void OneOrderRcHpfInit(OneOrderRcHpfHander* hander,float cutoff_fre,float sampling);
+float OneOrderRcHpfFun(OneOrderRcHpfHander *hander);
 
 #endif