CDU2FS_message_4.cpp

00001 // L. van der Kolk, ELVEDEKA, Holland 
00002 // File:  CDU2FS_message_4.cpp 
00003 //
00004 // -- Message handling from CDU to FS --
00005 
00006 #include "mbed.h"
00007 #include "MODSERIAL.h"
00008 #include "keys.h"
00009 #include "debug_lvdk.h" // : debug mode control
00010 
00011 extern MODSERIAL USB;
00012 extern MODSERIAL SERIAL_DEBUG;
00013 extern int CDU_FS_interface;
00014 
00015 int key_hit_ID = 0;   // : number of key that was hit, 0 = no hit of any key. ( global flag )
00016 
00017 char key_message[25]   =  "$PCDUKEY,";  // : setup begin of KEY message to FS
00018 char alive_message[25] =  "$PCDUOKE,";  // : setup begin of ALIVE message to FS
00019 
00020 
00021 void send_message_to_FS(char *message_string) {
00022     // Common fnction to send a created message string (KEY or OKE) to the FS.
00023     // Parameter is pointer to char string that has to be sent.
00024     // Interface can be USB port or Ethernet port.
00025     int i = 0;
00026     if ( CDU_FS_interface == 0 ) {  // : messages will be sent out by USB port
00027         while (  message_string[i] != '\0' ) {
00028                    USB.putc(message_string[i]);
00029                    i++;
00030         }
00031     }
00032     if ( CDU_FS_interface == 1 )  { 
00033      // Messages will be sent out by Ehternet interface
00034      // - Not implemented -
00035     }
00036 }
00037 
00038 
00039 void Send_ALIVE_message(int seconds){
00040     int i;
00041     char byte_read;
00042     char exor_byte = 0;
00043      //Create alive message:
00044         i = 9; // : i points to first place after "$PCDUOKE,"
00045         // Add seconds in 2 dec digits and a '*' char :
00046         sprintf(&alive_message[i],"%02d*",seconds); 
00047         // Calculate checksum now : 
00048         i = 1; // : i points to first place after '$'
00049         do { byte_read = alive_message[i];
00050              if (byte_read == '*') break; // : exclude '*' from exor calculation
00051              exor_byte = exor_byte ^ byte_read;
00052              i++;
00053         } while ( i < 20 );
00054         i++;  // : i now points to first digit of checksum after '*'
00055         // Add exor_byte in 2 hex chars (with upper case A-F) and a CR + LF:
00056         sprintf(&alive_message[i],"%02X\r\n",exor_byte); // : + extra NULL char added by sprintf 
00057         send_message_to_FS(alive_message); // : send message to defined CDU-FS interface
00058         
00059 }
00060 
00061 void Send_KEY_message(int key_nr) {
00062         // Function creates a valid KEY message out of key_nr parameter.
00063         // Based on key_nr, a key char string is looked up and added to the message.
00064         // After adding a checksum, the total KEY message will be sent.
00065         int i;
00066         char byte_read;
00067         char exor_byte = 0;
00068         //  Create key message, starting with "$PCDUKEY," message header
00069         i = 9; // : i points to first position after "$PCDUKEY," message header 
00070         // Add key string to message string including '*' 
00071         
00072         if ( key_nr != 0 && key_nr < max_keys_CDUpanel ) {
00073              strcpy(&key_message[i],key_value[key_nr]); 
00074             // Calculate checksum now : 
00075             i = 1; // : i points to first place after '$' in message
00076             do { byte_read = key_message[i];
00077                 if (byte_read == '*') break; // : exclude '*' from calculation
00078                 exor_byte = exor_byte ^ byte_read;
00079                 i++;
00080             } while ( i < 20 );
00081             i++;  // : i now points to first digit of checksum after '*'
00082             // Add exor_byte in 2 hex digits and a CR + LF:
00083             sprintf(&key_message[i],"%02X\r\n",exor_byte); // : extra NULL char added by sprintf
00084             send_message_to_FS(key_message); // : send message to defined CDU-FS interface 
00085         } 
00086 }           
00087         
00088