Diff: main.cpp

Revision:

0:9dfac5da16a9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Jan 25 00:05:16 2011 +0000
@@ -0,0 +1,38 @@
+#include "mbed.h"
+
+// MaxSonar EZ1 test program
+// by Michael Shimniok http://www.bot-thoughts.com/
+//
+// Based on datasheet here: http://www.maxbotix.com/uploads/LV-MaxSonar-EZ1-Datasheet.pdf
+// Reads from AN (analog) pin connected to mbed p20, assumes 3.3V supply to EZ1 module.
+//
+// mbed -> EZ1
+// -----------
+// VOUT -> +5
+// GND  -> GND
+// p20  -> AN
+//
+
+AnalogIn ain(p20);
+Serial pc(USBTX, USBRX); // tx, rx
+
+int main() {
+    float adc, volts, inches;
+    int feet, in;
+    
+    pc.baud(115200);
+    
+    while (1){
+        adc = ain.read();           // read analog as a float
+        volts = adc * 3.3;          // convert to volts
+        inches = volts / 0.0064;    // 3.3V supply: 6.4mV per inch
+        feet = (int) inches / 12;   // inches to feet (trunc)
+        in = (int) inches % 12;     // remainder -> in(ches)
+        
+        pc.printf("%8.2f adc %8.2fV %8.2f in %d'%d\"\n", adc, volts, inches, feet, in);
+
+        wait(0.05);                 // 20Hz update rate ; note we aren't truly synchronized to the device or anything...   
+    }
+}
+
+