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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Copyright (c) 04.2007 Holger Buss

// + Nur für den privaten Gebrauch

// + www.MikroKopter.com

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Es gilt für das gesamte Projekt (Hardware, Software, Binürfiles, Sourcecode und Dokumentation),

// + dass eine Nutzung (auch auszugsweise) nur für den privaten und nicht-kommerziellen Gebrauch zulüssig ist.

// + Sollten direkte oder indirekte kommerzielle Absichten verfolgt werden, ist mit uns (info@mikrokopter.de) Kontakt

// + bzgl. der Nutzungsbedingungen aufzunehmen.

// + Eine kommerzielle Nutzung ist z.B.Verkauf von MikroKoptern, Bestückung und Verkauf von Platinen oder Bausützen,

// + Verkauf von Luftbildaufnahmen, usw.

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Werden Teile des Quellcodes (mit oder ohne Modifikation) weiterverwendet oder verüffentlicht,

// + unterliegen sie auch diesen Nutzungsbedingungen und diese Nutzungsbedingungen incl. Copyright müssen dann beiliegen

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Sollte die Software (auch auszugesweise) oder sonstige Informationen des MikroKopter-Projekts

// + auf anderen Webseiten oder Medien verüffentlicht werden, muss unsere Webseite "http://www.mikrokopter.de"

// + eindeutig als Ursprung verlinkt und genannt werden

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Keine Gewühr auf Fehlerfreiheit, Vollstündigkeit oder Funktion

// + Benutzung auf eigene Gefahr

// + Wir übernehmen keinerlei Haftung für direkte oder indirekte Personen- oder Sachschüden

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Die Portierung der Software (oder Teile davon) auf andere Systeme (ausser der Hardware von www.mikrokopter.de) ist nur

// + mit unserer Zustimmung zulüssig

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Die Funktion printf_P() unterliegt ihrer eigenen Lizenz und ist hiervon nicht betroffen

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// + Redistributions of source code (with or without modifications) must retain the above copyright notice,

// + this list of conditions and the following disclaimer.

// +   * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived

// +     from this software without specific prior written permission.

// +   * The use of this project (hardware, software, binary files, sources and documentation) is only permittet

// +     for non-commercial use (directly or indirectly)

// +     Commercial use (for example: selling of MikroKopters, selling of PCBs, assembly, ...) is only permitted

// +     with our written permission

// +   * If sources or documentations are redistributet on other webpages, out webpage (http://www.MikroKopter.de) must be

// +     clearly linked as origin

// +   * porting to systems other than hardware from www.mikrokopter.de is not allowed

// +  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

// +  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

// +  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

// +  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

// +  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

// +  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

// +  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

// +  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

// +  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

// +  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

// +  POSSIBILITY OF SUCH DAMAGE.

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

#include <avr/io.h>

#include <avr/interrupt.h>

#include <avr/wdt.h>

#include <avr/pgmspace.h>

#include <stdarg.h>

#include <string.h>

#include "eeprom.h"

#include "menu.h"

#include "timer0.h"

#include "uart0.h"

#include "rc.h"

#include "externalControl.h"

#include "output.h"

#include "attitude.h"

#ifdef USE_MK3MAG

#include "mk3mag.h"

#endif

#define FC_ADDRESS 1

#define NC_ADDRESS 2

#define MK3MAG_ADDRESS 3

#define FALSE	0

#define TRUE	1

//int8_t test __attribute__ ((section (".noinit")));

uint8_t request_verInfo = FALSE;

uint8_t request_externalControl = FALSE;

uint8_t request_display = FALSE;

uint8_t request_display1 = FALSE;

uint8_t request_debugData = FALSE;

uint8_t request_data3D = FALSE;

uint8_t request_debugLabel = 255;

uint8_t request_PPMChannels = FALSE;

uint8_t request_motorTest = FALSE;

uint8_t request_variables = FALSE;

uint8_t displayLine = 0;

volatile uint8_t txd_buffer[TXD_BUFFER_LEN];

volatile uint8_t rxd_buffer_locked = FALSE;

volatile uint8_t rxd_buffer[RXD_BUFFER_LEN];

volatile uint8_t txd_complete = TRUE;

volatile uint8_t receivedBytes = 0;

volatile uint8_t *pRxData = 0;

volatile uint8_t rxDataLen = 0;

uint8_t motorTestActive = 0;

uint8_t motorTest[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

uint8_t confirmFrame;

typedef struct {

	int16_t Heading;

}__attribute__((packed)) Heading_t;

DebugOut_t debugOut;

Data3D_t data3D;

uint16_t debugData_timer;

uint16_t data3D_timer;

uint16_t debugData_interval = 0; // in 1ms

uint16_t data3D_interval = 0; // in 1ms

#ifdef USE_MK3MAG

int16_t compass_timer;

#endif

// keep lables in flash to save 512 bytes of sram space

const prog_uint8_t ANALOG_LABEL[32][16] = {

		//1234567890123456

		"AnglePitch      ", //0

		"AngleRoll       ",

		"AngleYaw        ",

		"GyroPitch       ",

		"GyroRoll        ",

		"GyroYaw         ", //5

		"AccPitch        ",

		"AccRoll         ",

		"AccZ            ",

		"AccPitch (angle)",

		"AccRoll (angle) ", //10

		"UBat            ",

		"Pitch Term      ",

		"Roll Term       ",

		"Yaw Term        ",

		"Throttle Term   ", //15

		"gyroP           ",

		"ControlAct/10   ",

        "Acc. Vector     ",

        "Max. Acc. Vector",

		"var0            ", //20

		"rc signal       ",

		"M1              ",

		"M2              ",

		"M3              ",

		"M4              ", //25

		"ControlYaw      ",

		"Airpress. Range ",

		"DriftCompPitch  ",

		"DriftCompRoll   ",

		"Altitude        ", //30

		"AirpressADC     " };

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

/*              Initialization of the USART0                    */

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

void usart0_init(void) {

	uint8_t sreg = SREG;

	uint16_t ubrr = (uint16_t) ((uint32_t) SYSCLK / (8 * USART0_BAUD) - 1);

	// disable all interrupts before configuration

	cli();

	// disable RX-Interrupt

	UCSR0B &= ~(1 << RXCIE0);

	// disable TX-Interrupt

	UCSR0B &= ~(1 << TXCIE0);

	// set direction of RXD0 and TXD0 pins

	// set RXD0 (PD0) as an input pin

	PORTD |= (1 << PORTD0);

	DDRD &= ~(1 << DDD0);

	// set TXD0 (PD1) as an output pin

	PORTD |= (1 << PORTD1);

	DDRD |= (1 << DDD1);

	// USART0 Baud Rate Register

	// set clock divider

	UBRR0H = (uint8_t) (ubrr >> 8);

	UBRR0L = (uint8_t) ubrr;

	// USART0 Control and Status Register A, B, C

	// enable double speed operation in

	UCSR0A |= (1 << U2X0);

	// enable receiver and transmitter in

	UCSR0B = (1 << TXEN0) | (1 << RXEN0);

	// set asynchronous mode

	UCSR0C &= ~(1 << UMSEL01);

	UCSR0C &= ~(1 << UMSEL00);

	// no parity

	UCSR0C &= ~(1 << UPM01);

	UCSR0C &= ~(1 << UPM00);

	// 1 stop bit

	UCSR0C &= ~(1 << USBS0);

	// 8-bit

	UCSR0B &= ~(1 << UCSZ02);

	UCSR0C |= (1 << UCSZ01);

	UCSR0C |= (1 << UCSZ00);

	// flush receive buffer

	while (UCSR0A & (1 << RXC0))

		UDR0;

	// enable interrupts at the end

	// enable RX-Interrupt

	UCSR0B |= (1 << RXCIE0);

	// enable TX-Interrupt

	UCSR0B |= (1 << TXCIE0);

	// initialize the debug timer

	debugData_timer = setDelay(debugData_interval);

	// unlock rxd_buffer

	rxd_buffer_locked = FALSE;

	pRxData = 0;

	rxDataLen = 0;

	// no bytes to send

	txd_complete = TRUE;

#ifdef USE_MK3MAG

	compass_timer = setDelay(220);

#endif

	versionInfo.SWMajor = VERSION_MAJOR;

	versionInfo.SWMinor = VERSION_MINOR;

	versionInfo.SWPatch = VERSION_PATCH;

	versionInfo.protoMajor = VERSION_SERIAL_MAJOR;

	versionInfo.protoMinor = VERSION_SERIAL_MINOR;

	// restore global interrupt flags

	SREG = sreg;

}

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

/* USART0 transmitter ISR                                       */

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

ISR(USART0_TX_vect) {

	static uint16_t ptr_txd_buffer = 0;

	uint8_t tmp_tx;

	if (!txd_complete) { // transmission not completed

		ptr_txd_buffer++; // die [0] wurde schon gesendet

		tmp_tx = txd_buffer[ptr_txd_buffer];

		// if terminating character or end of txd buffer was reached

		if ((tmp_tx == '\r') || (ptr_txd_buffer == TXD_BUFFER_LEN)) {

			ptr_txd_buffer = 0; // reset txd pointer

			txd_complete = 1; // stop transmission

		}

		UDR0 = tmp_tx; // send current byte will trigger this ISR again

	}

	// transmission completed

	else

		ptr_txd_buffer = 0;

}

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

/* USART0 receiver               ISR                            */

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

ISR(USART0_RX_vect) {

	static uint16_t checksum;

	static uint8_t ptr_rxd_buffer = 0;

	uint8_t checksum1, checksum2;

	uint8_t c;

	c = UDR0; // catch the received byte

	if (rxd_buffer_locked)

		return; // if rxd buffer is locked immediately return

	// the rxd buffer is unlocked

	if ((ptr_rxd_buffer == 0) && (c == '#')) { // if rxd buffer is empty and syncronisation character is received

		rxd_buffer[ptr_rxd_buffer++] = c; // copy 1st byte to buffer

		checksum = c; // init checksum

	}

#if 0

	else if (ptr_rxd_buffer == 1) { // handle address

		rxd_buffer[ptr_rxd_buffer++] = c; // copy byte to rxd buffer

		checksum += c; // update checksum

	}

#endif

	else if (ptr_rxd_buffer < RXD_BUFFER_LEN) { // collect incomming bytes

		if (c != '\r') { // no termination character

			rxd_buffer[ptr_rxd_buffer++] = c; // copy byte to rxd buffer

			checksum += c; // update checksum

		} else { // termination character was received

			// the last 2 bytes are no subject for checksum calculation

			// they are the checksum itself

			checksum -= rxd_buffer[ptr_rxd_buffer - 2];

			checksum -= rxd_buffer[ptr_rxd_buffer - 1];

			// calculate checksum from transmitted data

			checksum %= 4096;

			checksum1 = '=' + checksum / 64;

			checksum2 = '=' + checksum % 64;

			// compare checksum to transmitted checksum bytes

			if ((checksum1 == rxd_buffer[ptr_rxd_buffer - 2]) && (checksum2

					== rxd_buffer[ptr_rxd_buffer - 1])) {

				// checksum valid

				rxd_buffer[ptr_rxd_buffer] = '\r'; // set termination character

				receivedBytes = ptr_rxd_buffer + 1;// store number of received bytes

				rxd_buffer_locked = TRUE; // lock the rxd buffer

				// if 2nd byte is an 'R' enable watchdog that will result in an reset

				if (rxd_buffer[2] == 'R') {

					wdt_enable(WDTO_250MS);

				} // Reset-Commando

			} else { // checksum invalid

				rxd_buffer_locked = FALSE; // unlock rxd buffer

			}

			ptr_rxd_buffer = 0; // reset rxd buffer pointer

		}

	} else { // rxd buffer overrun

		ptr_rxd_buffer = 0; // reset rxd buffer

		rxd_buffer_locked = FALSE; // unlock rxd buffer

	}

}

// --------------------------------------------------------------------------

void Addchecksum(uint16_t datalen) {

	uint16_t tmpchecksum = 0, i;

	for (i = 0; i < datalen; i++) {

		tmpchecksum += txd_buffer[i];

	}

	tmpchecksum %= 4096;

	txd_buffer[i++] = '=' + tmpchecksum / 64;

	txd_buffer[i++] = '=' + tmpchecksum % 64;

	txd_buffer[i++] = '\r';

	txd_complete = FALSE;

	UDR0 = txd_buffer[0]; // initiates the transmittion (continued in the TXD ISR)

}

// --------------------------------------------------------------------------

// application example:

// sendOutData('A', FC_ADDRESS, 2, (uint8_t *)&request_DebugLabel, sizeof(request_DebugLabel), label, 16);

/*

 void sendOutData(uint8_t cmd, uint8_t addr, uint8_t numofbuffers, ...) { // uint8_t *pdata, uint8_t len, ...

 va_list ap;

 uint16_t txd_bufferIndex = 0;

 uint8_t *currentBuffer;

 uint8_t currentBufferIndex;

 uint16_t lengthOfCurrentBuffer;

 uint8_t shift = 0;

 txd_buffer[txd_bufferIndex++] = '#';			// Start character

 txd_buffer[txd_bufferIndex++] = 'a' + addr;	        // Address (a=0; b=1,...)

 txd_buffer[txd_bufferIndex++] = cmd;			// Command

 va_start(ap, numofbuffers);

 while(numofbuffers) {

 currentBuffer = va_arg(ap, uint8_t*);

 lengthOfCurrentBuffer = va_arg(ap, int);

 currentBufferIndex = 0;

 // Encode data: 3 bytes of data are encoded into 4 bytes,

 // where the 2 most significant bits are both 0.

 while(currentBufferIndex != lengthOfCurrentBuffer) {

 if (!shift) txd_buffer[txd_bufferIndex] = 0;

 txd_buffer[txd_bufferIndex]  |= currentBuffer[currentBufferIndex] >> (shift + 2);

 txd_buffer[++txd_bufferIndex] = (currentBuffer[currentBufferIndex] << (4 - shift)) & 0b00111111;

 shift += 2;

 if (shift == 6) { shift=0; txd_bufferIndex++; }

 currentBufferIndex++;

 }

 }

 // If the number of data bytes was not divisible by 3, stuff

 //  with 0 pseudodata  until length is again divisible by 3.

 if (shift == 2) {

 // We need to stuff with zero bytes at the end.

 txd_buffer[txd_bufferIndex]  &= 0b00110000;

 txd_buffer[++txd_bufferIndex] = 0;

 shift = 4;

 }

 if (shift == 4) {

 // We need to stuff with zero bytes at the end.

 txd_buffer[txd_bufferIndex++] &= 0b00111100;

 txd_buffer[txd_bufferIndex]    = 0;

 }

 va_end(ap);

 Addchecksum(pt); // add checksum after data block and initates the transmission

 }

 */

void sendOutData(uint8_t cmd, uint8_t addr, uint8_t numofbuffers, ...) { // uint8_t *pdata, uint8_t len, ...

	va_list ap;

	uint16_t pt = 0;

	uint8_t a, b, c;

	uint8_t ptr = 0;

	uint8_t *pdata = 0;

	int len = 0;

	txd_buffer[pt++] = '#'; // Start character

	txd_buffer[pt++] = 'a' + addr; // Address (a=0; b=1,...)

	txd_buffer[pt++] = cmd; // Command

	va_start(ap, numofbuffers);

	if (numofbuffers) {

		pdata = va_arg(ap, uint8_t*);

		len = va_arg(ap, int);

		ptr = 0;

		numofbuffers--;

	}

	while (len) {

		if (len) {

			a = pdata[ptr++];

			len--;

			if ((!len) && numofbuffers) {

				pdata = va_arg(ap, uint8_t*);

				len = va_arg(ap, int);

				ptr = 0;

				numofbuffers--;

			}

		} else

			a = 0;

		if (len) {

			b = pdata[ptr++];

			len--;

			if ((!len) && numofbuffers) {

				pdata = va_arg(ap, uint8_t*);

				len = va_arg(ap, int);

				ptr = 0;

				numofbuffers--;

			}

		} else

			b = 0;

		if (len) {

			c = pdata[ptr++];

			len--;

			if ((!len) && numofbuffers) {

				pdata = va_arg(ap, uint8_t*);

				len = va_arg(ap, int);

				ptr = 0;

				numofbuffers--;

			}

		} else

			c = 0;

		txd_buffer[pt++] = '=' + (a >> 2);

		txd_buffer[pt++] = '=' + (((a & 0x03) << 4) | ((b & 0xf0) >> 4));

		txd_buffer[pt++] = '=' + (((b & 0x0f) << 2) | ((c & 0xc0) >> 6));

		txd_buffer[pt++] = '=' + (c & 0x3f);

	}

	va_end(ap);

	Addchecksum(pt); // add checksum after data block and initates the transmission

}

// --------------------------------------------------------------------------

void Decode64(void) {

	uint8_t a, b, c, d;

	uint8_t x, y, z;

	uint8_t ptrIn = 3;

	uint8_t ptrOut = 3;

	uint8_t len = receivedBytes - 6;

	while (len) {

		a = rxd_buffer[ptrIn++] - '=';

		b = rxd_buffer[ptrIn++] - '=';

		c = rxd_buffer[ptrIn++] - '=';

		d = rxd_buffer[ptrIn++] - '=';

		//if(ptrIn > ReceivedBytes - 3) break;

		x = (a << 2) | (b >> 4);

		y = ((b & 0x0f) << 4) | (c >> 2);

		z = ((c & 0x03) << 6) | d;

		if (len--)

			rxd_buffer[ptrOut++] = x;

		else

			break;

		if (len--)

			rxd_buffer[ptrOut++] = y;

		else

			break;

		if (len--)

			rxd_buffer[ptrOut++] = z;

		else

			break;

	}

	pRxData = &rxd_buffer[3];

	rxDataLen = ptrOut - 3;

}

// --------------------------------------------------------------------------

void usart0_processRxData(void) {

	// We control the motorTestActive var from here: Count it down.

	if (motorTestActive)

		motorTestActive--;

	// if data in the rxd buffer are not locked immediately return

	if (!rxd_buffer_locked)

		return;

	uint8_t tempchar[3];

	Decode64(); // decode data block in rxd_buffer

	switch (rxd_buffer[1] - 'a') {

	case FC_ADDRESS:

		switch (rxd_buffer[2]) {

#ifdef USE_MK3MAG

		case 'K':// compass value

		compassHeading = ((Heading_t *)pRxData)->Heading;

		// compassOffCourse = ((540 + compassHeading - compassCourse) % 360) - 180;

		break;

#endif

		case 't': // motor test

			if (rxDataLen > 20) {

				memcpy(&motorTest[0], (uint8_t*) pRxData, sizeof(motorTest));

			} else {

				memcpy(&motorTest[0], (uint8_t*) pRxData, 4);

			}

			motorTestActive = 255;

			externalControlActive = 255;

			break;

		case 'n':// "Get Mixer Table

			while (!txd_complete)

				; // wait for previous frame to be sent

			sendOutData('N', FC_ADDRESS, 1, (uint8_t *) &mixerMatrix, sizeof(mixerMatrix));

			break;

		case 'm':// "Set Mixer Table

			if (pRxData[0] == EEMIXER_REVISION) {

				memcpy(&mixerMatrix, (uint8_t*) pRxData, sizeof(mixerMatrix));

				mixerMatrix_writeToEEProm();

				while (!txd_complete)

					; // wait for previous frame to be sent

				tempchar[0] = 1;

			} else {

				tempchar[0] = 0;

			}

			sendOutData('M', FC_ADDRESS, 1, &tempchar, 1);

			break;

		case 'p': // get PPM channels

			request_PPMChannels = TRUE;

			break;

		case 'q':// request settings

			if (pRxData[0] == 0xFF) {

				pRxData[0] = getParamByte(PID_ACTIVE_SET);

			}

			// limit settings range

			if (pRxData[0] < 1)

				pRxData[0] = 1; // limit to 1

			else if (pRxData[0] > 5)

				pRxData[0] = 5; // limit to 5

			// load requested parameter set

			paramSet_readFromEEProm(pRxData[0]);

			tempchar[0] = pRxData[0];

			tempchar[1] = EEPARAM_REVISION;

			tempchar[2] = sizeof(staticParams);

			while (!txd_complete)

				; // wait for previous frame to be sent

			sendOutData('Q', FC_ADDRESS, 2, &tempchar, 3, (uint8_t *) &staticParams, sizeof(staticParams));

			break;

		case 's': // save settings

			if (!(MKFlags & MKFLAG_MOTOR_RUN)) // save settings only if motors are off

			{

				if ((1 <= pRxData[0]) && (pRxData[0] <= 5) && (pRxData[1]

						== EEPARAM_REVISION)) // check for setting to be in range and version of settings

				{

					memcpy(&staticParams, (uint8_t*) &pRxData[2], sizeof(staticParams));

					paramSet_writeToEEProm(pRxData[0]);

					tempchar[0] = getActiveParamSet();

					beepNumber(tempchar[0]);

				} else {

					tempchar[0] = 0; //indicate bad data

				}

				while (!txd_complete)

					; // wait for previous frame to be sent

				sendOutData('S', FC_ADDRESS, 1, &tempchar, 1);

			}

			break;

		default:

			//unsupported command received

			break;

		} // case FC_ADDRESS:

	default: // any Slave Address

		switch (rxd_buffer[2]) {

		case 'a':// request for labels of the analog debug outputs

			request_debugLabel = pRxData[0];

			if (request_debugLabel > 31)

				request_debugLabel = 31;

			break;

		case 'b': // submit extern control

			memcpy(&externalControl, (uint8_t*) pRxData, sizeof(externalControl));

			confirmFrame = externalControl.frame;

			externalControlActive = 255;

			break;

		case 'h':// request for display columns

			remoteKeys |= pRxData[0];

			if (remoteKeys)

				displayLine = 0;

			request_display = TRUE;

			break;

		case 'l':// request for display columns

			menuItem = pRxData[0];

			request_display1 = TRUE;

			break;

		case 'v': // request for version and board release

			request_verInfo = TRUE;

			break;

		case 'x':

			request_variables = TRUE;

			break;

		case 'g':// get external control data

			request_externalControl = TRUE;

			break;

		case 'd': // request for the debug data

			debugData_interval = (uint16_t) pRxData[0] * 10;

			if (debugData_interval > 0)

				request_debugData = TRUE;

			break;

		case 'c': // request for the 3D data

			data3D_interval = (uint16_t) pRxData[0] * 10;

			if (data3D_interval > 0)

				request_data3D = TRUE;

			break;

		default:

			//unsupported command received

			break;

		}

		break; // default:

	}

	// unlock the rxd buffer after processing

	pRxData = 0;

	rxDataLen = 0;

	rxd_buffer_locked = FALSE;

}

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

/* Routine für die Serielle Ausgabe                                     */

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

int16_t uart_putchar(int8_t c) {

	if (c == '\n')

		uart_putchar('\r');

	// wait until previous character was send

	loop_until_bit_is_set(UCSR0A, UDRE0);

	// send character

	UDR0 = c;

	return (0);

}

//---------------------------------------------------------------------------------------------

void usart0_transmitTxData(void) {

	if (!txd_complete)

		return;

	if (request_verInfo && txd_complete) {

		sendOutData('V', FC_ADDRESS, 1, (uint8_t *) &versionInfo, sizeof(versionInfo));

		request_verInfo = FALSE;

	}

	if (request_display && txd_complete) {

		LCD_printMenu();

		sendOutData('H', FC_ADDRESS, 2, &displayLine, sizeof(displayLine),

				&displayBuff[displayLine * 20], 20);

		displayLine++;

		if (displayLine >= 4)

			displayLine = 0;

		request_display = FALSE;

	}

	if (request_display1 && txd_complete) {

		LCD_printMenu();

		sendOutData('L', FC_ADDRESS, 3, &menuItem, sizeof(menuItem), &maxMenuItem,

				sizeof(maxMenuItem), displayBuff, sizeof(displayBuff));

		request_display1 = FALSE;

	}

	if (request_debugLabel != 0xFF) { // Texte für die Analogdaten

		uint8_t label[16]; // local sram buffer

		memcpy_P(label, ANALOG_LABEL[request_debugLabel], 16); // read lable from flash to sram buffer

		sendOutData('A', FC_ADDRESS, 2, (uint8_t *) &request_debugLabel,

				sizeof(request_debugLabel), label, 16);

		request_debugLabel = 0xFF;

	}

	if (confirmFrame && txd_complete) { // Datensatz ohne checksum bestätigen

		sendOutData('B', FC_ADDRESS, 1, (uint8_t*) &confirmFrame, sizeof(confirmFrame));

		confirmFrame = 0;

	}

	if (((debugData_interval && checkDelay(debugData_timer)) || request_debugData)

			&& txd_complete) {

		sendOutData('D', FC_ADDRESS, 1, (uint8_t *) &debugOut, sizeof(debugOut));

		debugData_timer = setDelay(debugData_interval);

		request_debugData = FALSE;

	}

	if (((data3D_interval && checkDelay(data3D_timer)) || request_data3D)

			&& txd_complete) {

		sendOutData('C', FC_ADDRESS, 1, (uint8_t *) &data3D, sizeof(data3D));

		data3D.anglePitch = (int16_t) ((10 * angle[PITCH])

				/ GYRO_DEG_FACTOR_PITCHROLL); // convert to multiple of 0.1°

		data3D.angleRoll = (int16_t) ((10 * angle[ROLL])

				/ GYRO_DEG_FACTOR_PITCHROLL); // convert to multiple of 0.1°

		data3D.heading = (int16_t) ((10 * yawGyroHeading) / GYRO_DEG_FACTOR_YAW); // convert to multiple of 0.1°

		data3D_timer = setDelay(data3D_interval);

		request_data3D = FALSE;

	}

	if (request_externalControl && txd_complete) {

		sendOutData('G', FC_ADDRESS, 1, (uint8_t *) &externalControl,

				sizeof(externalControl));

		request_externalControl = FALSE;

	}

#ifdef USE_MK3MAG

	if((checkDelay(Compass_Timer)) && txd_complete) {

		toMk3Mag.Attitude[0] = (int16_t)((10 * angle[PITCH]) / GYRO_DEG_FACTOR_PITCHROLL); // approx. 0.1 deg

		toMk3Mag.Attitude[1] = (int16_t)((10 * angle[ROLL]) / GYRO_DEG_FACTOR_PITCHROLL); // approx. 0.1 deg

		toMk3Mag.UserParam[0] = dynamicParams.userParams[0];

		toMk3Mag.UserParam[1] = dynamicParams.userParams[1];

		toMk3Mag.CalState = compassCalState;

		sendOutData('w', MK3MAG_ADDRESS, 1,(uint8_t *) &toMk3Mag,sizeof(toMk3Mag));

		// the last state is 5 and should be send only once to avoid multiple flash writing

		if(compassCalState > 4) compassCalState = 0;

		compass_timer = setDelay(99);

	}

#endif

	if (request_motorTest && txd_complete) {

		sendOutData('T', FC_ADDRESS, 0);

		request_motorTest = FALSE;

	}

	if (request_PPMChannels && txd_complete) {

		sendOutData('P', FC_ADDRESS, 1, (uint8_t *) &PPM_in, sizeof(PPM_in));

		request_PPMChannels = FALSE;

	}

	if (request_variables && txd_complete) {

		sendOutData('X', FC_ADDRESS, 1, (uint8_t *) &variables, sizeof(variables));

		request_variables = FALSE;

	}

}