Diff: main.cpp

Revision:

0:52c8d2aa9944

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Feb 27 02:34:05 2013 +0000
@@ -0,0 +1,73 @@
+#include "mbed.h"
+
+#define PING_ERR    0xFFFF
+
+Timer timer1;
+Serial pc(USBTX, USBRX); // tx, rx 
+
+
+uint16_t moving_ave_5point(uint16_t data)
+{
+    static uint16_t tmp[5] = {0};
+    static uint32_t sum = 0;
+    uint8_t i;
+    uint8_t count;
+    
+    sum -= tmp[4];
+    sum += data;
+    tmp[4] = tmp[3];
+    tmp[3] = tmp[2];
+    tmp[2] = tmp[1];
+    tmp[1] = tmp[0];
+    tmp[0] = data;
+    
+    
+    count = 0;
+    for(i=0; i<5; i++){
+        if(tmp[i] == PING_ERR){
+            return PING_ERR;
+        }
+    }
+    
+    return sum/5;
+}
+
+
+uint16_t readPing (void)
+{
+    
+    DigitalOut PingPinOut(p13);
+    PingPinOut = 1;
+    wait_us(10);
+    PingPinOut = 0;
+    DigitalIn PingPin(p13);
+    //PingPin.mode(PullUp);
+    timer1.reset();
+    while(PingPin == 0){
+        if(timer1.read_us() > 1000){   //1ms以上応答なし
+            //pc.printf("1ms\n");
+            return PING_ERR;
+        }
+    } 
+    timer1.reset();
+    while(PingPin == 1){
+        if(timer1.read_us() > 18500){  //18.5ms以上のパルス
+            //printf("18.5ms\n");
+            return PING_ERR;
+        }
+    } 
+    
+    return timer1.read_us();
+}
+
+int main(void)
+{
+
+    timer1.start();
+    
+    for(;;){
+        pc.printf("%d\n",moving_ave_5point(readPing()));
+        
+        wait_us(200);
+    }
+}