#include <string.h>

#define IBUS_BUFFSIZE 32 // Max iBus packet size (2 byte header, 14 channels x 2 bytes, 2 byte checksum)
#define IBUS_MAXCHANNELS 10
static uint8_t ibusIndex = 0;
static uint8_t ibus[IBUS_BUFFSIZE] = {0};
static uint16_t rcValue[IBUS_MAXCHANNELS];

void setup()
{
Serial.begin(115200);

digitalWrite(13, HIGH); //Flash on rx update

Serial.println(“setup done!”);
}

void loop()
{
readRx();
UpdateOutput();
}

void UpdateOutput()
{
}
void readRx()
{
uint8_t i;

if (Serial.available())
{
uint8_t val = Serial.read();
// Look for 0x2040 as start of packet
if (ibusIndex == 0 && val != 0x20) {
return;
}
if (ibusIndex == 1 && val != 0x40) {
ibusIndex = 0;
return;
}

if (ibusIndex < IBUS_BUFFSIZE) ibus[ibusIndex] = val;
ibusIndex++;

if (ibusIndex == IBUS_BUFFSIZE)
{
digitalWrite(13,LOW);
}

ibusIndex = 0;
rcValue[0] = (ibus[ 3] << 8) + ibus[ 2];
rcValue[1] = (ibus[ 5] << 8) + ibus[ 4];
rcValue[2] = (ibus[ 7] << 8) + ibus[ 6];
rcValue[3] = (ibus[ 9] << 8) + ibus[ 8];
rcValue[4] = (ibus[11] << 8) + ibus[10];
rcValue[5] = (ibus[13] << 8) + ibus[12];
rcValue[6] = (ibus[15] << 8) + ibus[14];
rcValue[7] = (ibus[17] << 8) + ibus[16];
rcValue[8] = (ibus[19] << 8) + ibus[18];
rcValue[9] = (ibus[21] << 8) + ibus[20];
digitalWrite(13,HIGH);
return;
}
}
}