atomic

#include <util/atomic.h>

ATOMIC_BLOCK(ATOMIC_RESTORESTATE)

__disable_interrupt();

__enable_interrupt();

EEPROM

#include <EEPROM.h>

#define flash SEGMENT_D

else 
	current_protocol = constrain(EEPROM.read(ee_PROTOCOL_ID),0,PROTO_END-1);      
// update eeprom 
EEPROM.update(ee_PROTOCOL_ID, current_protocol);

// update eeprom 
Flash.write(flash+ee_PROTOCOL_ID, & current_protocol,1);

void set_txid(bool renew)
{
    uint8_t i;
    for(i=0; i<4; i++)
        transmitterID[i] = EEPROM.read(ee_TXID0+i);
    if(renew || (transmitterID[0]==0xFF && transmitterID[1]==0x0FF)) {
        for(i=0; i<4; i++) {
            transmitterID[i] = random() & 0xFF;
            EEPROM.update(ee_TXID0+i, transmitterID[i]); 
        }            
    }
}

void set_txid(bool renew)
{
    uint8_t i;
    unsigned char p;
    for(i=0; i<4; i++) {
        Flash.read(flash+ee_TXID0+i,&p,1);
        transmitterID[i] =p;
    }
	Flash.read(flash+ee_PROTOCOL_ID,&p,1);
    current_protocol = constrain(p,0,PROTO_END-1);
	Flash.erase(flash);
    if(renew || (transmitterID[0]==0xFF && transmitterID[1]==0x0FF)) {
        for(i=0; i<4; i++) {
            transmitterID[i] = random(0xff) & 0xFF;
            p = transmitterID[i];
            Flash.write(flash+ee_TXID0+i, &p,1); 
        }            
    }else{
        for(i=0; i<4; i++) {
            p = transmitterID[i];
            Flash.write(flash+ee_TXID0+i, &p,1); 
        }  	
	}
}

#define PPM_pin   2  // PPM in
//SPI Comm.pins with nRF24L01
#define MOSI_pin  3  // MOSI - D3
#define SCK_pin   4  // SCK  - D4
#define CE_pin    5  // CE   - D5
#define MISO_pin  A0 // MISO - A0
#define CS_pin    A1 // CS   - A1
#define ledPin    13 // LED  - D13

#define PPM_pin   P1_5  // PPM in
//SPI Comm.pins with nRF24L01
#define MOSI_pin  P2_0  // MOSI 
#define SCK_pin   P2_1  // SCK  
#define CE_pin    P2_2  // CE 
#define MISO_pin  P2_3 // MISO 
#define CS_pin    P2_4 // CS   
#define ledPin    P1_4 // LED  

#define MOSI_on PORTD |= _BV(3)  // PD3
#define MOSI_off PORTD &= ~_BV(3)// PD3
#define SCK_on PORTD |= _BV(4)   // PD4
#define SCK_off PORTD &= ~_BV(4) // PD4
#define CE_on PORTD |= _BV(5)    // PD5
#define CE_off PORTD &= ~_BV(5)  // PD5
#define CS_on PORTC |= _BV(1)    // PC1
#define CS_off PORTC &= ~_BV(1)  // PC1
// SPI input
#define  MISO_on (PINC & _BV(0)) // PC0

#define MOSI_on P2OUT |= _BV(0)// P2_0
#define MOSI_off P2OUT &= ~_BV(0)// P2_0
#define SCK_on P2OUT |= _BV(1)// P2_1
#define SCK_off P2OUT &= ~_BV(1)// P2_1
#define CE_on P2OUT |= _BV(2)// P2_2
#define CE_off P2OUT &= ~_BV(2)// P2_2
#define CS_on P2OUT |= _BV(4)// P2_4
#define CS_off P2OUT &= ~_BV(4) // P2_4
// SPI input
#define  MISO_on (P2IN & _BV(3)) // P2_3

#define _BV(val) 1<<val

randomSeed((analogRead(A4) & 0x1F) | (analogRead(A5) << 5));

randomSeed((analogRead(A0) & 0x1F) | (analogRead(A1) << 5));

attachInterrupt(PPM_pin - 2, ISR_ppm, CHANGE);

attachInterrupt(PPM_pin , ISR_ppm, CHANGE);

TCCR1A = 0;  //reset timer1
TCCR1B = 0;
TCCR1B |= (1 << CS11);  //set timer1 to increment every 1 us @ 8MHz, 0.5 us @16MHz

TACTL = TASSEL_2 + ID_3 + MC_2 + TACLR; //16000000 / 8

counterPPM = TCNT1;
TCNT1 = 0;

counterPPM = TAR;
TAR = 0;

random()

random() & 0xFF; 

random(0xFF);

random() % 0x42;

random(0x41);

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