Softwareserial.h Library Page

| Method | Description | |--------|-------------| | begin(baud) | Initializes the software serial port. | | available() | Returns number of bytes ready to read. | | read() | Reads one byte (-1 if none). | | write(data) | Sends a byte (or string via print() / println() ). | | listen() | Enables this port for reception (if multiple ports exist). | | isListening() | Checks if this port is active. | | overflow() | Returns true if data was lost due to buffer overflow (64-byte buffer). |

For ESP8266/ESP32, note that they have a different SoftwareSerial implementation (often renamed or not available due to better hardware serial options). softwareserial.h library

// Send a test pattern void testSoftwareSerialBaud(long baud) SoftwareSerial ss(10, 11); ss.begin(baud); ss.print("U"); delay(1000); | | write(data) | Sends a byte (or

void setup() port1.begin(9600); port2.begin(9600); port1.listen(); // port1 is active | | overflow() | Returns true if data

void setup() Serial.begin(9600); ss.begin(9600); ss.println("Hello"); delay(10); while(ss.available()) Serial.write(ss.read());

: It uses a fixed receive buffer of 256 bytes , which can fill up quickly if data isn't read promptly. The "Gotchas" & Limitations