Hardware & Devices

Luc Pattyn wrote:

If your idea of software development is strictly PC-based, and you are
unfamiliar with embedded systems, it would be a challenge to get things working
without having the observability and debugging tools you have in say Visual Studio...

const int PORT = 0x378;   // base address of LPT1 on

const char ENABLE = 1;  // syn enable   PC Pin # 2
const char CLOCK = 2;   // syn clock    PC Pin # 3
const char DATA  = 4;   // syn data     PC Pin # 4

char state;

void OutputP(long data, int n, bool bSync)
{
   // take enable low
   state &= ~ENABLE;

   outp(PORT, state);

   long current_bit = pow(2,n-1);

   for (int i = 0 ; i < n ; i++)
     {
     // set data bit
     if (data & current_bit)
       state |= DATA;
     else
       state &= ~DATA;
     // output data bit
     outp(PORT, state);

     // clock it
     state |= CLOCK;
     outp(PORT, state);

     state &= ~CLOCK;
     outp(PORT, state);

     current_bit /= 2;
     }


   // take enable high
   state = ENABLE;  // ensures all other lines are low
   if (bSync)
   	state |= SYNC;
   outp(PORT, state);
}