Track.cpp

00001 #include "Track.h"
00002 
00003 Track::Track () : trackpin(p20), lcd(p22, p21, p23, p24, p25, p26), myled1(LED1)
00004 {
00005     //ctor
00006     address = 0;
00007     inst = 0;
00008     myled1 = 1;
00009 }
00010 
00011 Track::~Track()
00012 {
00013     //dtor
00014 }
00015 
00016 void Track::DCC_send_command(unsigned int address, unsigned int inst, unsigned int repeat_count)
00017 {
00018     unsigned __int64 command = 0x0000000000000000; // __int64 is the 64-bit integer type
00019     unsigned __int64 temp_command = 0x0000000000000000;
00020     unsigned __int64 prefix = 0x3FFF; // 14 "1" bits needed at start
00021     unsigned int error = 0x00; //error byte
00022     //calculate error detection byte with xor
00023     error = address ^ inst;
00024     //combine packet bits in basic DCC format
00025     command = (prefix<<28)|(address<<19)|(inst<<10)|((error)<<1)|0x01;
00026     //printf("\n\r %llx \n\r",command);
00027     int i=0;
00028 //repeat DCC command lots of times
00029     while(i < repeat_count) {
00030         temp_command = command;
00031 //loops through packet bits encoding and sending out digital pulses for a DCC command
00032         for (int j=0; j<64; j++) {
00033             if((temp_command&0x8000000000000000)==0) { //test packet bit
00034                 //send data for a "0" bit
00035                 trackpin=0;
00036                 wait_us(100);
00037                 trackpin=1;
00038                 wait_us(100);
00039             } else {
00040                 //send data for a "1"bit
00041                 trackpin=0;
00042                 wait_us(58);
00043                 trackpin=1;
00044                 wait_us(58);
00045             }
00046             // next bit in packet
00047             temp_command = temp_command<<1;
00048         }
00049         i++;
00050     }
00051 }