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Operate two softwar...
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[Solved] Operate two software serials on esp8266

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I have to gather data from two sensors which work using uart(rx,tx) communication. I have to integrate them with esp8266 but the problem is that I can't have 2 software serials using esp8266. I searched for libraries which can allow 2 software serials on esp8266 but none of them support a baud rate of 115200. One of my sensors baud rate is 115200 and I can't change it. I saw a code on the official softwareserial library documentation and read the example of "2 ports using software serial" and implemented on esp8266 but it's not working. Kindly guide me (I only have to use esp8266 and the those sensors and can't change them now). Please help me(it's a bit urgent task), anyone having any solution on esp8266. Thanks

My code:


#include <SoftwareSerial.h>

#define sh_TX D8
#define sh_RX D7

const int bufferSize = 29;
float currenttemp = 0.0,prevtemp = 0.0;

char receivedData[bufferSize] ; char prevreceivedData[bufferSize];
char temperature_data[8] = {'\0'}; char prevtemperature_data[8] = {'\0'};
char humidity_data[6] = {'\0'}; char prevhumidity_data[6] = {'\0'};

const unsigned long interval = 2000; // Interval in milliseconds (2 seconds)
unsigned long previousMillis = 0;

int count = 1;

#define TX D6
#define RX D5

SoftwareSerial witSerial(RX, TX);
SoftwareSerial SHT20Serial(sh_RX, -1);

int data;
void setup() {
pinMode(RX, INPUT);
pinMode(TX, OUTPUT);

void loop() {
if (SHT20Serial.isListening()) {
Serial.println("portOne is listening!");
int bytesRead = SHT20Serial.readBytesUntil('\n\r', receivedData, bufferSize - 1); //\r\n\r

if (isnan(bytesRead)) {
Serial.println("Failed to read from SHT20 sensor!");
receivedData[bytesRead] = '\0'; // Null-terminate the string clears the string

Serial.print("Received data: ");
Serial.println(receivedData); Serial.println();

int temperature_index = 7;
int i;
for (i = 0; i < 5; i++) { //prev: 7
temperature_data[i] = receivedData[temperature_index + i];

int humidity_index = 23;
for (i = 0; i < 5; i++) {
humidity_data[i] = receivedData[humidity_index + i];

Serial.println("Temperature data: ");
Serial.println("Humidity data: ");
} else {
Serial.println("portOne is not listening!");

if (witSerial.isListening()) {
Serial.println("portTwo is listening!");
while (witSerial.available()>0) {
} else {
Serial.println("portTwo is not listening!");


Famed Member Admin
Joined: 11 years ago
Posts: 2726

I'm on vacation at the moment, so I do not have much time to respond.
However ... you may want to look in using an ESP32 instead (if that is an option).
The cool part is that an ESP32 has 2 cores which can be used as such even with Arduino code.
Maybe (!) this way you can handle two software serial ports?
(may have to read up on it though)

harrypeter reacted