Revision 0:56a10c93329f, committed 2010-10-11

Comitter:

pd0wm

Date:

Mon Oct 11 18:46:18 2010 +0000

Commit message:

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SerialBuffered.cpp	Mon Oct 11 18:46:18 2010 +0000
@@ -0,0 +1,108 @@
+
+#include "mbed.h"
+#include "SerialBuffered.h"
+ 
+extern Serial loggerSerial;
+ 
+SerialBuffered::SerialBuffered( size_t bufferSize, PinName tx, PinName rx ) : Serial(  tx,  rx ) 
+{
+    m_buffSize = 0;
+    m_contentStart = 0;
+    m_contentEnd = 0;
+    m_timeout = 1.0;
+   
+    
+    attach( this, &SerialBuffered::handleInterrupt );
+    
+    m_buff = (uint8_t *) malloc( bufferSize );
+    if( m_buff == NULL )
+    {
+        //loggerSerial.printf("SerialBuffered - failed to alloc buffer size %d\r\n", (int) bufferSize );
+    }
+    else
+    {
+        m_buffSize = bufferSize;
+    }
+}
+
+
+SerialBuffered::~SerialBuffered()
+{
+    if( m_buff )
+        free( m_buff );
+}
+
+void SerialBuffered::setTimeout( float seconds )
+{
+    m_timeout = seconds;
+}
+    
+size_t SerialBuffered::readBytes( uint8_t *bytes, size_t requested )
+{
+    int i = 0;
+
+    for( ; i < requested; )
+    {
+        int c = getc();
+        if( c < 0 )
+            break;
+        bytes[i] = c;
+        i++;
+    }
+    
+    return i;
+        
+}
+
+
+int SerialBuffered::getc()
+{
+    m_timer.reset();
+    m_timer.start();
+    while( m_contentStart == m_contentEnd )
+    {
+      
+
+        wait_ms( 1 );
+        if( m_timeout > 0 &&  m_timer.read() > m_timeout )
+            return EOF;
+    }
+
+    m_timer.stop();
+   
+    uint8_t result = m_buff[m_contentStart++];
+    m_contentStart =  m_contentStart % m_buffSize;
+
+   
+    return result;    
+}
+
+
+int SerialBuffered::readable()
+{
+    return m_contentStart != m_contentEnd ;
+}
+
+void SerialBuffered::handleInterrupt()
+{
+    
+    while( Serial::readable())
+    {
+        if( m_contentStart == (m_contentEnd +1) % m_buffSize)
+        {
+           loggerSerial.printf("SerialBuffered - buffer overrun, data lost!\r\n" );
+           Serial::getc();
+
+        }
+        else
+        {
+          
+            m_buff[ m_contentEnd ++ ] = Serial::getc();
+            m_contentEnd = m_contentEnd % m_buffSize;
+            
+           
+           
+        }
+    }
+}
+

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SerialBuffered.h	Mon Oct 11 18:46:18 2010 +0000
@@ -0,0 +1,39 @@
+#pragma once
+
+// This is a buffered serial reading class, using the serial interrupt introduced in mbed library version 18 on 17/11/09
+
+// In the simplest case, construct it with a buffer size at least equal to the largest message you 
+// expect your program to receive in one go.
+
+class SerialBuffered : public Serial
+{
+public:
+    SerialBuffered( size_t bufferSize, PinName tx, PinName rx );
+    virtual ~SerialBuffered();
+    
+    int getc();     // will block till the next character turns up, or return -1 if there is a timeout
+    
+    int readable(); // returns 1 if there is a character available to read, 0 otherwise
+    
+    void setTimeout( float seconds );    // maximum time in seconds that getc() should block 
+                                         // while waiting for a character
+                                         // Pass -1 to disable the timeout.
+    
+    size_t readBytes( uint8_t *bytes, size_t requested );    // read requested bytes into a buffer, 
+                                                             // return number actually read, 
+                                                             // which may be less than requested if there has been a timeout
+    
+
+private:
+    
+    void handleInterrupt();
+    
+   
+    uint8_t *m_buff;            // points at a circular buffer, containing data from m_contentStart, for m_contentSize bytes, wrapping when you get to the end
+    uint16_t  m_contentStart;   // index of first bytes of content
+    uint16_t  m_contentEnd;     // index of bytes after last byte of content
+    uint16_t m_buffSize;
+    float m_timeout;
+    Timer m_timer;
+
+};
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Oct 11 18:46:18 2010 +0000
@@ -0,0 +1,21 @@
+#include "mbed.h"
+#include "SerialBuffered.h"
+
+
+Serial loggerSerial(USBTX, USBRX);
+
+
+DigitalOut uart_activity(LED2);
+
+int main() {
+    SerialBuffered *b = new SerialBuffered( 1001, p28, p27);
+    b->baud( 9600 );
+    b->setTimeout( 5 );
+    while (1) {
+        if (b.readable()) {
+            loggerSerial.putc(b.getc());
+        }
+
+    }
+
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Mon Oct 11 18:46:18 2010 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/e2ac27c8e93e