Subversion Repositories Projects

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

// ** Spektrum Diversity v2.1 - use up to 4 satellite receivers **

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

// ** Spektrum DSMX Binding Extension by Johannes Stein 2011/03 **

// **                                                           **

// **  3 Pulses = DSM2 1024/22ms                                **

// **  5 Pulses = DSM2 2048/11ms                                **

// **  7 Pulses = DSMX 22ms                                     **

// **  9 Pulses = DSMX 11ms                                     **

// **                                                           **

// ** Target: An Atmel ATtiny2313 (RC-Oscillator @ 8 MHz)       **

// **         controls a 74HC151 Multiplexer                    **

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

// ** It monitors the data from 4 satellite receivers and       **

// ** connects a valid one to the output via the multiplexer    **

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

// ** LED-Modes during startup                                  **

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

// ** LED fast flash: Waiting for first signal                  **

// **                                                           **

// ** LED-Modes during operation                                **

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

// ** LED flash 1x - 4x: Shows which channel is active every 2s **

// ** LED ON after flash: FAILURE - A used signal was lost      **

// **                                                           **

// ** LED-Modes after Self-Test and pressed button              **

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

// ** LED flashes at 1 Hz: Everything is fine                   **

// ** LED flashes some times: Times flashed -> damaged Channel# **

// ** LED off: check voltage(regulator), button or firmware     **

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

// ** (c) 2010-0xFFFF Stefan Pendsa                             **

// ** License: don't know - use it and have fun                 **

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

#include <avr/io.h>

#include <avr/eeprom.h>

#include <avr/interrupt.h>

#include <util/delay.h>

#define LED_OFF	PORTD |= 1 << PD0

#define LED_ON	PORTD &= ~(1 << PD0)

volatile unsigned char Timer0Event = 0;

volatile unsigned int Timer1Event;

volatile unsigned char BlinkCode = 0;

volatile unsigned char failure = 0;

unsigned char eedummy EEMEM;								// Dummy-Variable for Address 0 in EEPROM

unsigned char eecheck EEMEM;								// Check-Variable

unsigned char bind;											// Bind-Pulse-Counter (in RAM)

unsigned char eebind EEMEM;									// Bind-Pulse-Counter (in EEPROM)

ISR(TIMER0_OVF_vect)										// Triggered every 32,768 msec

{

	if (Timer0Event > 64)									// Max. 64*32 msec = 2,097152 sec

	{

		Timer0Event = 0;

		LED_OFF;

	}

	if(Timer0Event == 0 && BlinkCode > 0) LED_ON;

	else if(Timer0Event == 4 && BlinkCode > 0) LED_OFF;

	else if(Timer0Event == 8 && BlinkCode > 1) LED_ON;

	else if(Timer0Event == 12 && BlinkCode > 1) LED_OFF;

	else if(Timer0Event == 16 && BlinkCode > 2) LED_ON;

	else if(Timer0Event == 20 && BlinkCode > 2) LED_OFF;

	else if(Timer0Event == 24 && BlinkCode > 3) LED_ON;

	else if(Timer0Event == 28 && BlinkCode > 3) LED_OFF;

	else if(Timer0Event == 35 && failure == 1) LED_ON;

	else if(Timer0Event == 55 && failure == 1) LED_OFF;

	Timer0Event++;

}

ISR(TIMER1_OVF_vect)										// Triggered every 8,192 msec

{

	Timer1Event++;

}

void SelectSat(unsigned char sat)

{

	PORTD = (PORTD & 0b1100111) | (sat << 3);				// Select the input for 74HC151

	_delay_us(10);											// Wait for stable state

}

void ResetTimer1(void)

{

	TCNT1H = 0;

	TCNT1L = 0;

	Timer1Event = 0;

}

void Binding(void)											// Binding sequence (for Spektrum sats only)

{

	unsigned char i = 0;

	DDRB = 0b11110000;										// Sat-Pins to output

	_delay_ms(80);											// Let them time to boot up

	for (i=0;i<bind;i++)									// Send negative 100µs pulses to all sat's

	{

		PORTB = 0b00000000;

		_delay_us(100);

		PORTB = 0b11110000;

		_delay_us(100);

	}

	for (i=0;i<bind;i++)									// Flash the number of used pulses to the LED

	{

		LED_ON;

		_delay_ms(100);

		LED_OFF;

		_delay_ms(250);

	}

	DDRB = 0b00000000;										// Sat-Pins to input again

	bind += 2;

	if (bind > 9) bind = 3;									// 3, 5, 7, 9 pulses, then start with 3 again

	eeprom_write_byte(&eebind, bind);						// Save increased bind-pulse-counter for next binding.

	_delay_ms(500);

}

void Testing(void)											// Self Test

{

	unsigned char error = 0;

	unsigned char i = 0;

	DDRB = 0b11110000;										// Port B Output for satellites, Input for feedback

	PORTB = 0b01010000;										// Test Pattern

	SelectSat(0);

	if (!(PINB & (1<<PB3))) error = 1;

	SelectSat(1);

	if (PINB & (1<<PB3)) error = 2;

	SelectSat(2);

	if (!(PINB & (1<<PB3))) error = 3;

	SelectSat(3);

	if (PINB & (1<<PB3)) error = 4;

	PORTB = 0b10100000;										// Another (inverted) Test Pattern

	SelectSat(0);

	if (PINB & (1<<PB3)) error = 1;

	SelectSat(1);

	if (!(PINB & (1<<PB3))) error = 2;

	SelectSat(2);

	if (PINB & (1<<PB3)) error = 3;

	SelectSat(3);

	if (!(PINB & (1<<PB3))) error = 4;

	DDRB = 0b00000000;										// Port B Input again

	while (PIND & (1<<PD6));								// Wait for Bind-Switch

	while(1)												// Never return

	{

		if (error == 0)										// When no error occured -> LED flashes at 1 Hz

		{

			LED_ON;

			_delay_ms(100);

			LED_OFF;

			_delay_ms(900);

		}

		else

		{

			for (i=0;i<error;i++)							// When error occured -> Flash-Out the Errorcode

			{

				LED_ON;

				_delay_ms(100);

				LED_OFF;

				_delay_ms(400);

			}

			_delay_ms(1000);

		}

	}

}

int main(void)

{

	unsigned char i = 0;

	unsigned char active[4];

	unsigned char active_lo[4];

	unsigned char active_hi[4];

	unsigned char sat = 99;

	DDRB = 0b00000000;										// Port B Input for satellites and feedback

	DDRD = 0b0011001;										// Port D Output for MUX and LED, Input for Switch & Test

	PORTB = 0b11110000;										// Port B Pullup's for (unused) satellites

	PORTD = 0b1100001;										// Port D Pullup's for Switch & Test, LED off

    if (eeprom_read_byte(&eecheck) != 0x84)					// Invalid Data in EEPROM -> initialize

	{

		eeprom_write_byte(&eecheck, 0x84);

		bind = 3;

		eeprom_write_byte(&eebind, bind);

	}

	else bind = eeprom_read_byte(&eebind);					// Valid Data in EEPROM -> read bind-pulse-counter

	if (!(PIND & (1<<PD5))) Testing();						// Initiate Self-Test when Test-Pad is low

	if (!(PIND & (1<<PD6))) Binding();						// Initiate Binding when Bind-Button is pressed

	for (i=0;i<4;i++)										// Reset active-arrays

	{

		active[i] = 0;

		active_lo[i] = 0;

		active_hi[i] = 0;

	}

	_delay_ms(100);

	TCCR0B = ( 1 << CS00 ) | ( 1 << CS02 );					// Timer0 Prescaler = 1024 -> 32,768 msec

	TCCR1B = ( 1 << CS10 );									// Timer1 Prescaler = 1 -> 8,192 msec

	TIMSK = ( 1 << TOIE0 ) | ( 1 << TOIE1 );				// Timer0+1 Overflow Interrupt Enable

	sei();													// Global Interrupts enable

	ResetTimer1();

	while(sat == 99)										// Wait for first signal

	{

		if (Timer1Event == 10) LED_ON;						// Blink while waiting

		if (Timer1Event == 20)

		{

			LED_OFF;

			Timer1Event = 0;

		}

		while(Timer1Event < 3)								// Check active satellites (for 3*8=24ms)

		{

			for (i=0;i<4;i++)

			{

				if (PINB & (1<<(i+4))) active_hi[i] = 1;

				else active_lo[i] = 1;

			}

		}

		for (i=0;i<4;i++)									// When an input had low AND high signals, mark it as active

		{

			if (active_lo[i] == 1 && active_hi[i] == 1) active[i] = 1;

		}

		for (i=0;i<4;i++)									// Select first active satellite

		{

			if (active[i] == 1)

			{

				SelectSat(i);

				sat = i;

				BlinkCode = i+1;

				break;

			}

		}

	}

	while(1)												// Main-Loop

	{

		for (i=0;i<4;i++)									// Reset active-arrays

		{

			active[i] = 0;

			active_lo[i] = 0;

			active_hi[i] = 0;

		}

		ResetTimer1();

		while(Timer1Event < 3)								// Check active satellites (for 3*8=24ms)

		{

			for (i=0;i<4;i++)

			{

				if (PINB & (1<<(i+4))) active_hi[i] = 1;

				else active_lo[i] = 1;

			}

		}

		for (i=0;i<4;i++)									// When an input had low AND high signals, mark it as active

		{

			if (active_lo[i] == 1 && active_hi[i] == 1) active[i] = 1;

		}

		if (active[0] == 0 && active[1] == 0 && active[2] == 0 && active[3] == 0 && sat != 99)

		{

			failure = 1;									// Set Failure-LED when the signal is lost completely

			BlinkCode = 0;

			sat = 99;

		}

		for (i=0;i<4;i++)									// Select active satellite (priorized)

		{

			if (active[i] == 1)

			{

				SelectSat(i);

				if (sat != i) failure = 1;					// Set Failure-LED when the active satellite changes

				sat = i;

				BlinkCode = i+1;

				break;

			}

		}

		if (!(PIND & (1<<PD6))) failure = 0;				// Reset Failure-LED when Bind-Button is pressed

	}

}