Softwareserial.h Arduino Library Download May 2026
| Library/Approach | Best for | |----------------|-----------| | HardwareSerial | Primary serial, high baud rates. | | NeoSWSerial | Reliable reception on two pins at up to 57600 baud. | | AltSoftSerial | High-performance, but uses fixed timer pins (8 & 9 on Uno). | | SerialPort (Mega) | Multiple hardware ports (Serial1, Serial2, Serial3). | | I2C/SPI to UART bridge (e.g., SC16IS750) | Add many hardware UARTs externally. | Problem: Read NMEA sentences from a GPS module (4800 baud) and transmit them over Bluetooth (9600 baud) to a smartphone.
void setup() mySerial.begin(9600);
void loop() mySerial.println("Hello");
| Scenario | Action | |----------|--------| | Standard Arduino IDE | No action needed; just #include <SoftwareSerial.h> | | Update library | Boards Manager → Update Arduino AVR Boards | | Manual install | Download ZIP from GitHub → unzip → place in sketchbook/libraries/SoftwareSerial | | PlatformIO | Add arduino-libraries/SoftwareSerial to lib_deps |
#include <SoftwareSerial.h> SoftwareSerial gps(4, 3); // RX, TX for GPS SoftwareSerial ble(6, 5); // RX, TX for Bluetooth softwareserial.h arduino library download
SoftwareSerial gps(4, 5); SoftwareSerial ble(6, 7); void setup() gps.begin(9600); ble.begin(115200); // may be unreliable at this baud rate
If the sketch compiles without errors, the library is correctly installed. 6.1 Basic Initialization SoftwareSerial ss(RX_PIN, TX_PIN); ss.begin(baudRate); 6.2 Sending Data Use write() , print() , println() , write(uint8_t) , etc. | | SerialPort (Mega) | Multiple hardware ports
| Port | Pins | |------|------| | PCINT0 | 8 | | PCINT1 | 9 | | PCINT2 | 10, 11, 12, 13 | | PCINT3 | A0–A5 (14–19) |