ESP8266 two serial ports with SoftwareSerial library

In certain cases we need to use more than one Serial port in the case of arduino, I use the arduino mega 2560 which has 4 serial ports including the programming port, in the case of arduino’s as the nano has a single programming port and as a solution Have created the softwareserial library, given the incompatibility of certain functions the softwareserial library for arduino does not work on esp8266.

Softwareserial Library

I have tested with ESP8266 NodeMCU and SoftwareSerial library of the espsoftwareserial repository created or supplied by plerup thanks for your contribution to the community.

Recommendations

In the case that these libraries that create a uart in code must be taken into account that at high speeds it is possible to have bit errors since they use interrupts and the microcontroller you are in many tasks at a time, in my case and the tests that I have I configured the port at Maximo 9600 Bauds, it is a relatively low speed but I consider it to be safe.

Buy it here: Module ESP8266 NodeMCU v3 WIFI 4Mb

Test

To verify the operation of the softwareserial library, I downloaded the library for esp and I have temporarily replaced the serial software version for arduino.

Tutorial ESP8266 12E NodeMCU & SoftwareSerial

Arduino IDE Code

This test creates a bridge between the 2 serial ports.

#include
SoftwareSerial mySerial(13, 15, false, 256);

//Mas informacion http://pdacontrolen.com/
// More info http://pdacontrolen.com/

void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
Serial.println("Connect! - Conexion ");
// set the data rate for the SoftwareSerial port
mySerial.begin(9600);
mySerial.println("Connect! - Conexion SOFTWARESERIAL");
}

void loop() // run over and over
{
if (mySerial.available())
Serial.write(mySerial.read());
if (Serial.available())
mySerial.write(Serial.read());
}