ReceiveTest.ino

// AltSoftSerial Receive Test
//
// Transmit data with Serial1 and try to receive
// it with AltSoftSerial.  You must connect a wire
// from Serial1 TX to AltSoftSerial RX.
 
#include <AltSoftSerial.h>
 
AltSoftSerial altser;
const int mybaud = 9600;
 
// Board            Serial1 TX   AltSoftSerial RX
// -----            ----------   ----------------
// Teensy 3.x            1              20
// Teensy 2.0            8 (D3)         10 (C7)
// Teensy++ 2.0          3 (D3)          4 (D4)
// Arduino Leonardo      1              13
// Arduino Mega         18              48
 
// Serial1 on AVR @ 16 MHz minimum baud is 245
// Serial1 on Teensy 3.2 @ 96 MHz minimum baud is 733
 
// This example code is in the public domain.
 
byte sentbyte;
unsigned long prevmillis;
byte testbyte=0xF0;
 
void setup()
{
    delay(200);
    Serial.begin(9600);
    while (!Serial) ;  // wait for Arduino Serial Monitor
    Serial1.begin(mybaud); // connect a wire from TX1
    altser.begin(mybaud);   // to AltSoftSerial RX
    Serial.println("AltSoftSerial Receive Test");
    prevmillis = millis();
}
 
void loop()
{
    // transmit a test byte on Serial 1
    if (millis() - prevmillis > 250) {
        sentbyte = testbyte++;
        Serial1.write(sentbyte);
        prevmillis = millis();
    }
    // attempt to receive it by AltSoftSerial
    if (altser.available() > 0) {
        byte b = altser.read();
        Serial.println(b);
        if (b != sentbyte) {
            Serial.println("***** ERROR *****");
        }
    }
}