// filename  Master.C  Jonathan W. Valvano, April 17, 2000
// COP reset will be disabled by COPCTL=0;
/*  RS485 half-duplex multiport network  
  Hardware: 
     Adapt812 MC68HC812A4 SCI1 serial port
     RS-485 half-duplex network to other Adapt812s
     6812 PS3/TXD1 connected to SP483 DI data in 
     6812 PS2/RXD1 connected to SP483 RO receive out
     6812 PE6      connected to SP483 DE 1 enables transmission 
     6812 PE5      connected to SP483 RE 0 enables receiver 
     SP483 A-A, B-B, ground-ground */

#include "HC12.h"
#include "SCI0.H"
#include "SCI1.H"

char letter;
int XMTerror; // OK(0), COLLISION(1) or TIMEOUT(2) 
int RCVerror; // OK(0), Bit3=OR, Bit2=NF, Bit1=FE, Bit0=PF 

void main(void){  
  SCI0Init();
  SCI1Init();
  COPCTL=0;     // turn off COP
  XMTerror=0;
  SCI0OutString("Adapt812 RS485 Half-duplex demo 4/17/00 -JWV\n");
  SCI0OutString("Type input to transmit\n"); 

  while(1){
    XMTerror=0;
    if(SCI0InStatus()){          // check if new input from PC
      PORTT^=0x40;               // toggle bit 6
  	  letter=SCI0In();           // data from PC keyboard 
  	  XMTerror=SCI1Out(letter);  // transmit on network to other 6812s 
	}
    if(SCI1InStatus()){          // check if new input from network
      letter=SCI1In(&RCVerror);  // data from network
      SCI0Out(letter);           // display on destination PCs
	  if(RCVerror&PF)
        SCI0OutString("\nParity error\n");
      if(RCVerror&NF)
        SCI0OutString("\nNoise error\n");
      if(RCVerror&FE)
        SCI0OutString("\nFraming error\n");
      if(RCVerror&OR)
        SCI0OutString("\nOverrun error\n");
    }
	if(XMTerror&TIMEOUT)
      SCI0OutString("\nTimeout\n");
	if(XMTerror&COLLISION)
      SCI0OutString("\nCollision\n");
	if(XMTerror&PARITYERROR)
      SCI0OutString("\nParity Error\n");
  }
}
#include "SCI0.C"
#include "SCI1.C"

extern void _start();	/* entry point in crt12.s */
#pragma abs_address:0xfffe
void (*reset_vectors[])() = { _start };
#pragma end_abs_address