/**************************************************************************

	master.c

   Z-World, 2001
	This sample program is for the BL20XX series controllers.
	
	Connect circuitry as	described in the User Manual in the main
	hardware chapter under Serial Communication.
	
	This program demonstrates a simple RS485 transmission
	of lower case letters to a slave controller.  The slave
	will send back converted upper case letters back to the
	master controller and displayed in STDIO window.
	
	Use slave.c to program the slave controller.
		
	Make the following connections:

		Master to  Slave
		485+ <---> 485+							
		485- <---> 485-							
		GND  <---> GND

**************************************************************************/

// serial D buffer size
#define DINBUFSIZE  255
#define DOUTBUFSIZE 255

nodebug
void msDelay(unsigned int ams)
{
	auto unsigned long t0;
	
	for (t0=MS_TIMER; MS_TIMER<ams+t0;);
}

///////////////////////////////////////////////////////////////////////////
main()
{
	auto int nIn1;
	auto char cOut;
	auto int sync;

	
	brdInit();
	
	serDopen(19200);	//set baud rate first
	serDwrFlush();		//clear Rx and Tx data buffers 
	serDrdFlush();

	// Sync up to the slave controller
	sync = FALSE;
	while(!sync)
	{
		cOut = 0x55;
		ser485Tx();							//	enable transmitter
		serDputc ( cOut );				//	send lowercase byte
		while (serDgetc() == -1);		//	wait for echo
		ser485Rx();							// disable transmitter
		msDelay(5);
		if((nIn1 = serDgetc ()) == -1)	//	check for reply
		{
			printf ("Waiting to sync up to the other controller\r", cOut, nIn1 );		
		}
		else
		{
			if(nIn1 == cOut)
			{
				sync = TRUE;
			}
		}
	}
			
	while (1)
	{
		for (cOut='a';cOut<='z';++cOut)
		{
			ser485Tx();										//	enable transmitter
			serDputc ( cOut );							//	send lowercase byte
			while (serDgetc() == -1);					//	wait for echo
			ser485Rx();										// disable transmitter
			
			while ((nIn1 = serDgetc ()) == -1);		//	wait for reply
			if (nIn1 == (toupper(cOut)))
				printf ("\n\rUpper case %c is %c", cOut, nIn1 );		
		}
	}
}
///////////////////////////////////////////////////////////////////////////