问题
I am doing an Autonomous Car project and I have a NEO 6M GPS module, I am using an ESp32 as the board, the module works fine with Arduino and Nodemcu. but not with ESP32, the reason being it not supporting software serial, so I took help from https://www.youtube.com/watch?v=GwShqW39jlE&feature=emb_title
I added hardware serial but still, there is no output I have provided the code below
#include<HardwareSerial.h>//No extra libray installed
#define RXD2 16
#define TXD2 17
HardwareSerial gps_serial(2);
void setup() {
Serial.begin(115200);
Serial.printf("LETS START");
gps_serial.begin(115200, SERIAL_8N1, RXD2, TXD2);
}
void loop() {
while (gps_serial.available()) {
Serial.print(char(gps_serial.read())); // read from gps, write to serial debug port
Serial.print("I am here");
}
}
The output on the serial monitor is LETS START
The other code which worked on other boards is also provided below, edited to work in ESP32
#include <WiFi.h>
//#include <WiFiClient.h>
#include <WiFiServer.h>
#include <TinyGPS++.h> // library for GPS module
//#include <SoftwareSerial.h>
//#include <ESP8266WiFi.h>
TinyGPSPlus gps; // The TinyGPS++ object
//SoftwareSerial ss(4, 5); // The serial connection to the GPS device
HardwareSerial Serial2(2);
const char* ssid = "***********"; //ssid of your wifi
const char* password = "***********"; //password of your wifi
float latitude , longitude;
int year , month , date, hour , minute , second;
String date_str , time_str , lat_str , lng_str;
int pm;
WiFiServer server(80);
void setup()
{ Serial2.begin(115200);
Serial.begin(115200);
//ss.begin(9600);
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password); //connecting to wifi
while (WiFi.status() != WL_CONNECTED)// while wifi not connected
{
delay(500);
Serial.print("."); //print "...."
}
Serial.println("");
Serial.println("WiFi connected");
server.begin();
Serial.println("Server started");
Serial.println(WiFi.localIP()); // Print the IP address
}
void loop()
{
while (Serial2.available() > 0) //while data is available
if (gps.encode(Serial2.read())) //read gps data
{
if (gps.location.isValid()) //check whether gps location is valid
{
latitude = gps.location.lat();
lat_str = String(latitude , 6); // latitude location is stored in a string
longitude = gps.location.lng();
lng_str = String(longitude , 6); //longitude location is stored in a string
}
if (gps.date.isValid()) //check whether gps date is valid
{
date_str = "";
date = gps.date.day();
month = gps.date.month();
year = gps.date.year();
if (date < 10)
date_str = '0';
date_str += String(date);// values of date,month and year are stored in a string
date_str += " / ";
if (month < 10)
date_str += '0';
date_str += String(month); // values of date,month and year are stored in a string
date_str += " / ";
if (year < 10)
date_str += '0';
date_str += String(year); // values of date,month and year are stored in a string
}
if (gps.time.isValid()) //check whether gps time is valid
{
time_str = "";
hour = gps.time.hour();
minute = gps.time.minute();
second = gps.time.second();
minute = (minute + 30); // converting to IST
if (minute > 59)
{
minute = minute - 60;
hour = hour + 1;
}
hour = (hour + 5) ;
if (hour > 23)
hour = hour - 24; // converting to IST
if (hour >= 12) // checking whether AM or PM
pm = 1;
else
pm = 0;
hour = hour % 12;
if (hour < 10)
time_str = '0';
time_str += String(hour); //values of hour,minute and time are stored in a string
time_str += " : ";
if (minute < 10)
time_str += '0';
time_str += String(minute); //values of hour,minute and time are stored in a string
time_str += " : ";
if (second < 10)
time_str += '0';
time_str += String(second); //values of hour,minute and time are stored in a string
if (pm == 1)
time_str += " PM ";
else
time_str += " AM ";
}
}
WiFiClient client = server.available(); // Check if a client has connected
if (!client)
{
return;
}
// Prepare the response
String s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n <!DOCTYPE html> <html> <head> <title>GPS DATA</title> <style>";
s += "a:link {background-color: YELLOW;text-decoration: none;}";
s += "table, th, td </style> </head> <body> <h1 style=";
s += "font-size:300%;";
s += " ALIGN=CENTER> GPS DATA</h1>";
s += "<p ALIGN=CENTER style=""font-size:150%;""";
s += "> <b>Location Details</b></p> <table ALIGN=CENTER style=";
s += "width:50%";
s += "> <tr> <th>Latitude</th>";
s += "<td ALIGN=CENTER >";
s += lat_str;
s += "</td> </tr> <tr> <th>Longitude</th> <td ALIGN=CENTER >";
s += lng_str;
s += "</td> </tr> <tr> <th>Date</th> <td ALIGN=CENTER >";
s += date_str;
s += "</td></tr> <tr> <th>Time</th> <td ALIGN=CENTER >";
s += time_str;
s += "</td> </tr> </table> ";
s += "</body> </html>";
client.print(s); // all the values are send to the webpage
delay(100);
}
I do get the IP address on the serial monitor when I run it but when I access that address the fields are blank. So what I understand is that the Serial communication with the GPS module is not working. I tried many other solutions on net but no use at all.
I am using ESP32 DevKit V1, 30 pins version
回答1:
Not knowing which ESP32 Module you use exactly, there are two show stoppers
NEO-6M GPS Module needs 5 V, ESP32 pins deliver max 3.6V - normaly 3.3V
Some ESP32 modules block certain pins to use them for SD card, camera, lcd or other on board features. So look up the datasheet of your esp32 board variant.
The code should be ok if HWSerial2 exists
If you use ESP32 version below 1.03 you have to define HWSerial,
ESP32 1.04 up this is not necessary any more
#define RXD2 16
#define TXD2 17
...
HardwareSerial Serial2(2);
...
Serial2.begin(115200, SERIAL_8N1, RXD2, TXD2);
and 5V power is supplied to the GSM module.
Edit 2: Credit to hcheung asking the most basic thing
The solution was the OP had RX to RX and TX to TX, instead of RX ESP pin to RX on GPS and vice versa.
So problem solved
来源：https://stackoverflow.com/questions/60421562/serial2-of-esp32-not-responding-neo-6m-gps