/****************************************************************
/* Program Name: DX70SGC.c
/*	Version: 1.0
/*	Date: 27 August 2002
/*
/*	This source was written by Zack Clobes, W0ZC for use
/*	with Alinco DX-70 Transceivers using SGC tuners.  It is
/*	free for all non-commerical use.  You may contact me
/*	at zack@clobes.net.
/*
/*	Periodic updates and/or modifications will be made
/*	available at www.rckara.org/.
/*
/*	While I trust this code with my own equipment, I make
/*	no warranty that it will function correctly in any given
/*	environment and will not be held resposible for data or
/*	property loss due to the failure of this code or 
/*	related hardware.
/***************************************************************/

#include <16f84.h>

#fuses XT,NOWDT
#use delay(clock=4000000)

#define SGC_TUNED PIN_A2
#define DX70_START PIN_B5
#define DX70_PTT PIN_B4
#define PIEZO PIN_B3

void chirp(void);
void beep_k(void);
void beep_bad_tune(void);

void main(void) {
	int iCnt;
	int iTuneStatus;	//0=not tuning, 1=tuning, 2=good match, 3=bad match
	int iSolidOn;
	int iChirp;
	int i;
	
	delay_ms(1000);	//wait for everything to power up
	beep_k();
		

	iTuneStatus = 0;	//we're not tuning

	while(1) {
		//wait in infinate loop for the tune_start to go high
		
		if (input(DX70_START)) {
			//we have a start tune
			output_high(DX70_PTT);	//key the transmitter
			
			delay_ms(1000);	//always tune at least 1 second
			chirp();
			
			//initialize the counter variables
			iCnt = 0;
			iChirp = 0;
			iTuneStatus = 1;	//we're starting to tune
			
			//start watching the tuned light
			//can't go longer than 200 because the DX-70 times out before the tuner
			while((iTuneStatus == 1) && (iCnt < 200)) {
				//loop until we're done tuning

				delay_ms(100);
				if (iChirp > 20) {
					chirp();		//chirp every 2 seconds
					iChirp = 0;
				}
				iCnt++;
				iChirp++;
				
				iSolidOn = 0;	//default the flag off
				if	(input(SGC_TUNED) == 0) {
					//the tuned light came on (went low)
					iSolidOn = 1;	//we had a trigger, now watch it
					for (i=0;i<10;i++) {
						//loop thru for 100ms to make sure we have a valid tune line (not line noise)
						if (input(SGC_TUNED) == 1) iSolidOn = 0;	//set the flag that we're not solid
						delay_ms(10);
					}
					iCnt++;	//we just spent 100ms in the loop above
				
					//if the line stayed high for the past 100ms, then the tuner is done
					if (iSolidOn) {
						output_low(DX70_PTT);	//shut the xmitter down - we're done with it
						//now wait to see if the light stays on, or if it's blinking
						iTuneStatus = 2;		//assume a good tune
						for (i=0;i<8;i++) {
							delay_ms(100);
							if (input(SGC_TUNED) != 0) {
								//it's blinking
								iTuneStatus = 3;	//bad tune
								i=8;		//break out of the loop
							}
						}
					}
				}


			}
			output_low(DX70_PTT);	//make sure the xmitter is off

			if (iTuneStatus == 2) {
				beep_k();		//good tune
			} else {
				beep_bad_tune();	//bad tune
			}
			iTuneStatus = 0;	//reset back to not tuning
		}
	}
}

void chirp(void) {
	//make a small chirp - as during the tuning process
	output_high(PIEZO);
	delay_ms(75);
	output_low(PIEZO);
}

void beep_k(void) {
	//send a K in morse to indicate finished tuning
	output_high(PIEZO);
	delay_ms(325);
	output_low(PIEZO);
	delay_ms(100);
	output_high(PIEZO);
	delay_ms(130);
	output_low(PIEZO);
	delay_ms(100);
	output_high(PIEZO);
	delay_ms(400);
	output_low(PIEZO);
}

void beep_bad_tune(void) {
	//send three longs to indicate a bad match
	output_high(PIEZO);
	delay_ms(750);
	output_low(PIEZO);
	delay_ms(500);
	output_high(PIEZO);
	delay_ms(750);
	output_low(PIEZO);
	delay_ms(500);
	output_high(PIEZO);
	delay_ms(750);
	output_low(PIEZO);
}