Diff: PulseManager.cpp

Revision:

0:67bcc374fa16

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PulseManager.cpp	Mon Aug 03 18:26:05 2015 +0000
@@ -0,0 +1,142 @@
+#include "PulseManager.h"
+
+PulseManager::PulseManager(PinName trigger, PinName echo):
+        startval(0), pulsetime(), runtime(), trigger(trigger), echo(echo)    {}
+
+
+PulseManager::~PulseManager() {}
+
+void PulseManager::write(int val) {
+    trigger = val;
+}
+
+void PulseManager::write_us(int val, int time)   {
+    // Write the complement of the high/low signal for a clean desired signal
+    trigger = !val;
+    wait_us(4);
+    
+    // Now write the desired signal for the given amount of time in us
+    trigger = val;
+    wait_us(time);
+    
+    // Write the complement again to end the signal write
+    trigger = !val;
+}
+
+int PulseManager::read_us()  {
+    // Reset the pulse timer
+    pulsetime.reset();
+    
+    // Wait for edge
+    startval = echo;
+    while (echo == startval)   {}
+    
+    // Measure pulse width
+    pulsetime.start();
+    while (echo != startval)  {}
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}
+
+int PulseManager::read_us(int timeout)   {
+    // Reset timers, start runtime timer to detect timeout
+    runtime.reset();
+    runtime.start();
+    pulsetime.reset();
+    
+    // Wait for edge
+    startval = echo;
+    while (echo == startval)  {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    
+    // Measure pulse width
+    pulsetime.start();
+    while (echo != startval)   {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}
+
+int PulseManager::read_high_us()  {
+    // Reset timer
+    pulsetime.reset();
+    
+    // Wait for next edge of echo signal
+    while (echo == 1) {}
+    while (echo == 0) {}
+    
+    // Measure pulse width of the echo pulse
+    pulsetime.start();
+    while (echo == 1) {}
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}
+
+int PulseManager::read_high_us(int timeout)  {
+    // Reset runtime timer for timeout detection
+    runtime.reset();
+    runtime.start();
+    
+    // Reset pulseTimer
+    pulsetime.reset();
+    
+    // Wait for next edge of echo signal
+    while (echo == 1) {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    while (echo == 0) {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    
+    // Measure pulse width of the echo pulse
+    pulsetime.start();
+    while (echo == 1) {
+        if (runtime.read_us() > timeout)   return -1;    
+    }
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}
+
+int PulseManager::read_low_us()   {
+    // Wait for next edge of echo signal
+    while (echo == 0) {
+    }
+    while (echo == 1) {
+    }
+    
+    // Measure pulse width of the echo pulse
+    pulsetime.start();
+    while (echo == 0) {}
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}
+
+int PulseManager::read_low_us(int timeout)   {
+    // Reset runtime timer for timeout detection
+    runtime.reset();
+    runtime.start();
+    
+    // Wait for next edge of echo signal
+    while (echo == 0) {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    while (echo == 1) {
+        if (runtime.read_us() > timeout)   return -1;
+    }
+    
+    // Measure pulse width of the echo pulse
+    pulsetime.start();
+    while (echo == 0) {
+        if (runtime.read_us() > timeout)   return -1;    
+    }
+    pulsetime.stop();
+    
+    return pulsetime.read_us();
+}