pipe serial1 -> serial and vice versa

serial_bridge

SYSTEM_MODE(MANUAL);

void setup() {
    Serial.begin(9600);
    Serial1.begin(9600);
    pinMode(D7, OUTPUT);
}

void loop() {
    if (Serial1.available()) {
        char c = Serial1.read();
        Serial.write(c);
        count++;
    }
    else if (Serial.available()) {
        char c = Serial.read();
        Serial1.write(c);
    }
}