Diff: main.cpp

Revision:

0:1de208404352

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Dec 29 21:21:56 2009 +0000
@@ -0,0 +1,173 @@
+#include "mbed.h"
+
+Serial pc(USBTX, USBRX); // tx, rx
+
+DigitalOut myled_4(LED4);
+DigitalOut myled_3(LED3);
+DigitalOut myled_2(LED2);
+DigitalOut myled_1(LED1);
+
+Timer serial_timeout;
+
+const int MAX_DELAY_BETWEEN_CHARCTERS_IN_MS = 2000;
+
+const int BAUD_RATE = 115200;
+
+const int CAPACITY_COMMAND       = 1;
+const int MISSING_DATA_COMMAND   = 2;
+const int DEVICE_TIMEOUT_COMMEND = 3;
+
+static int counter;
+
+static int length;
+static int curr_pos;
+
+static bool buffer_full;
+
+static int readCharTimed ()
+  {
+    serial_timeout.reset ();
+    while (!pc.readable ())
+      {
+        if (serial_timeout.read_ms () > MAX_DELAY_BETWEEN_CHARCTERS_IN_MS)
+          {
+            myled_1 = 1;
+            return -1;
+          }
+      }
+    return pc.getc ();
+  }
+
+int getCommand (int first_char)
+  {
+    buffer_full = false;
+    serial_timeout.start ();
+    int next_char = readCharTimed ();
+    if (next_char < 0)
+      {
+        myled_2 = 1;
+        return -1;
+      }
+    length = ((first_char << 8) + next_char) & 0xFFFF;
+    curr_pos = 1;
+    return readCharTimed ();  // This is the command (pos 0 in expected buffer)
+  }
+
+#define OUTPUT_TIMED
+
+void putByte (int c)
+  {
+#ifdef OUTPUT_TIMED
+    if (!buffer_full)
+      {
+        serial_timeout.start ();
+        while (true)
+          {
+            if (pc.writeable ())
+              {
+#endif
+                pc.putc (c);
+#ifdef OUTPUT_TIMED
+                break;
+              }
+            if (serial_timeout.read_ms () > MAX_DELAY_BETWEEN_CHARCTERS_IN_MS)
+              {
+                myled_1 = 1;
+                myled_4 = 1;
+                buffer_full = true;
+                break;
+              }
+          }
+      }
+#endif
+  }
+
+
+void putSuccessStatus ()
+  {
+    if (curr_pos != length)
+      {
+        myled_1 = 1;
+        myled_2 = 1;
+        myled_3 = 1;
+      }
+    putByte (0);
+  }
+
+
+void putShort (int v)
+  {
+    putByte (v >> 8);
+    putByte (v & 0xFF);
+  }
+
+
+void putString (char *string)
+  {
+    int len = strlen (string);
+    putShort (len);
+    for (int i = 0; i < len; i++)
+      {
+        pc.putc (string[i]);
+      }
+  }
+
+
+int getChar ()
+  {
+    if (curr_pos++ >= length)
+      {
+        myled_3 = 1;
+      }
+    return readCharTimed() & 0xFF;
+  }
+
+int getShort ()
+  {
+    int v = getChar () << 8;
+    return v + getChar ();
+  }
+
+int main()
+  {
+    pc.baud (BAUD_RATE);
+    while (1)
+      {
+        counter++;
+        switch (getCommand (pc.getc ()))
+          {
+            case CAPACITY_COMMAND:
+              int out_buffer_size;
+              out_buffer_size = getShort () & 0xFFFF;
+              int in_buffer_size;
+              in_buffer_size = getShort () & 0xFFFF;
+              while (in_buffer_size-- > 0)
+                {
+                  getChar ();
+                }
+              putSuccessStatus ();
+              putShort (out_buffer_size);
+              while (out_buffer_size-- > 0)
+                {
+                  putByte (0);
+                }    
+              break;
+
+            case MISSING_DATA_COMMAND:
+              getShort ();
+              putSuccessStatus ();
+              break;
+
+            case DEVICE_TIMEOUT_COMMEND:
+              wait (30);
+              putSuccessStatus ();
+              break;
+              
+            default:
+              myled_2 = 1;
+              pc.putc (7);
+              putString ("No such command...");
+          }
+      }
+  }
+