Revision 4:a615b75d4126, committed 2010-08-28

Comitter:

Blaze513

Date:

Sat Aug 28 07:59:29 2010 +0000

Parent:

3:05183e50a923

Commit message:

Changed in this revision

--- a/MB1210.cpp	Thu Aug 26 18:25:19 2010 +0000
+++ b/MB1210.cpp	Sat Aug 28 07:59:29 2010 +0000
@@ -13,6 +13,7 @@
         SerialInput = new Serial(NC, rx);
         SerialInput->baud(9600);
         SerialInput->format(8, Serial::None, 1);
+        SerialInput->attach(NULL, Serial::RxIrq);
         OperatingMode = 0x02;
     }
     if (an != NC)
@@ -66,14 +67,34 @@
 
 void MB1210::Mode(char Selection)
 {
+    if (SerialInput)
+    {
+        if (Selection & 0x08)
+        {
+            SerialInput->attach(this, &MB1210::Interrupt, Serial::RxIrq);
+        }
+        else
+        {
+            SerialInput->attach(NULL, Serial::RxIrq);
+        }
+            //attach or detach the interrupt function
+    }
+        //interrupts can only be generated if rx pin is connected
     if (SerialOutput)
     {
         SerialOutput->write(Selection & 0x04);
     }
+        //synchronous modes can only be set if tx pin is connected
     OperatingMode = Selection & 0x03;
 }
     //change the operating mode; SerialOutput controls synchronicity
 
+void MB1210::AttachInterruptBuffer(float* Buffer)
+{
+    InterruptBuffer = Buffer;
+}
+    //the user changes the pointer to their own storage area so they can use the interrupt
+
 void MB1210::RequestSyncRead()
 {
     if (SerialOutput)
@@ -120,12 +141,13 @@
             if (SerialInput)
             {
                 unsigned char i = 0;
-                while (SerialInput->readable() && !SerialInput->scanf("R%3d", &Range) && (i < 32))
+                while (SerialInput->readable() && !SerialInput->scanf("R%3f", &Range) && (i < 32))
                 {
                     SerialInput->getc();
                     i++;
                 }
-                return (float)Range * UnitFactor;
+                    //find R and parse the range out
+                return Range * UnitFactor;
             }
             else
             {
@@ -137,20 +159,15 @@
 }
     //OperatingMode switches to desired output method;
     //the result is scaled according to voltage, the speed of sound, and desired unit
-void MB1210::Read(char* Buffer)
+
+void MB1210::Interrupt()
 {
-    if (SerialInput)
-    {
-        unsigned char i = 0;
-        while (SerialInput->readable() && !SerialInput->scanf("R%3s", Buffer) && (i < 32))
-        {
-            SerialInput->getc();
-            i++;
-        }
-    }
+    *InterruptBuffer = Read();
+    DiscardSerialBuffer();
 }
-    //this overload is for serial only, regardless of selected mode;
-    //reads 3 ASCII character result into the given buffer
+    //this is called whenever an interrupt mode is
+    //set and a serial rx interrupt is generated;
+    //it writes to the user's data storage area
 
 MB1210::operator float()
 {

--- a/MB1210.h	Thu Aug 26 18:25:19 2010 +0000
+++ b/MB1210.h	Sat Aug 28 07:59:29 2010 +0000
@@ -21,12 +21,17 @@
         float UnitFactor;
         float PwmScalingFactor;
         float AnalogScalingFactor;
-        unsigned short Range;
+        float Range;
+        float* InterruptBuffer;
+
+        void Interrupt();
 
     public:
         MB1210(PinName pw, PinName an, PinName tx, PinName rx);
             //pulse width modulation input, analog input, serial output, serial input;
-            //specify NC if pin is not used
+            //specify NC if pin is not used;
+            //if the pulse width pin is used, interrupts will perform a
+            //few microseconds of calculations every time a reading is taken
         ~MB1210();
             //deallocates PwmInput, AnalogInput, SerialOutput, and SerailInput
         void SoundVelocity(float MetersPerSecond);
@@ -43,9 +48,19 @@
             //default is cm
         void Mode(char Selection);
             //argument sets operating mode;
-            //0 to 2 for synchronous modes, 4 to 6 for asynchronous modes;
-            //0 and 4 for pwm, 1 and 5 for analog, 2 and 6 for serial;
+            //set flag 0x08 to 0 for polled modes, or 1 for interrupt modes;
+            //set flag 0x04 to 0 for synchronous modes, or 1 for asynchronous modes;
+            //set flags 0x03 to 0 for pwm, 1 for analog, or 2 for serial;
+            //asynchronous modes generate pulse width interrupts, prepare an
+            //analog reading, and send a 5 byte serial reading every 99 ms;
+            //interrupt modes automatically read the range into the buffer provided
+            //by AttachInterruptBuffer with the selected input method every 99 ms
+            //if in an asynchronous mode, or 99 ms after RequestSyncRead is called;
+            //the rx pin must be connected to use an interrupt mode;
+            //the tx pin must be connected to use a synchronous mode;
             //default is 0
+        void AttachInterruptBuffer(float* Buffer);
+            //if interrupts are used, user must provide address to write result to
         void RequestSyncRead();
             //this tells the device to prepare a synchronous range reading;
             //must be called at least 99 ms before the reading is needed;
@@ -59,11 +74,6 @@
             //RequestSyncRead() must be called at least 99 ms
             //before this method can be called in a synchronous mode;
             //may be called at any time during asynchronous mode;
-        void Read(char* Buffer);
-            //overloaded to take advantage of Serial ASCII string output;
-            //Buffer must be 3 bytes; 3 digit ASCII number
-            //measures range in cm regardless of selected unit;
-            //uses serial input method regardless of selected mode.
         operator float();
             //shorthand for taking a range reading;
             //ex: "float reading = MB1210Object;"

--- a/main.cpp	Thu Aug 26 18:25:19 2010 +0000
+++ b/main.cpp	Sat Aug 28 07:59:29 2010 +0000
@@ -1,27 +1,29 @@
-#include "mbed.h"
-#include "MB1210.h"
-
-DigitalOut debugled(LED1);
-Serial Computer(USBTX, USBRX);
-
-MB1210 RangeFinder(p12, p15, p13, p14);
-                
-int main()
-{
-    Computer.baud(9600);
-    debugled = 0;
-    RangeFinder.Unit(39.370);//change units to inches
-    while(1)
-    {
-        debugled = !debugled;
-        RangeFinder.RequestSyncRead();//request a range reading
-        wait_ms(100);//wait for reading to be prepared
-        RangeFinder.Mode(0);//switch to PWM mode
-        Computer.printf("PWM reading: %f in | ", RangeFinder.Read());
-        RangeFinder.Mode(1);//switch to Analog mode
-        Computer.printf("Analog reading: %f in | ", RangeFinder.Read());
-        RangeFinder.Mode(2);//switch to serial mode
-        Computer.printf("Serial reading: %f in | ", RangeFinder.Read());
-        wait(0.9);
-    }
+#include "mbed.h"
+#include "MB1210.h"
+
+DigitalOut debugled(LED1);
+Serial Computer(USBTX, USBRX);
+
+MB1210 RangeFinder(p12, p15, p13, p14);
+float Range;
+int main()
+{
+    Computer.baud(9600);
+    debugled = 0;
+    RangeFinder.Unit(39.370);//change units to inches
+    RangeFinder.AttachInterruptBuffer(&Range);
+    RangeFinder.Mode(0x0A);
+    while(1)
+    {
+        debugled = !debugled;
+        RangeFinder.RequestSyncRead();//request a range reading
+        wait_ms(100);//wait for reading to be prepared
+        //RangeFinder.Mode(0);//switch to PWM mode
+        //Computer.printf("PWM reading: %f in | ", Range);
+        //RangeFinder.Mode(1);//switch to Analog mode
+        //Computer.printf("Analog reading: %f in | ", Range);
+        //RangeFinder.Mode(2);//switch to serial mode
+        Computer.printf("Serial reading: %f in | ", Range);
+        wait(0.9);
+    }
 }
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