I just connected an A6 GSM module and wrote a code to interact with it through the serial monitor connecting at 9600 baud rate. but the character "?" just keeps coming nonstop and nothing else works.
Here is my code:
#include<SoftwareSerial.h>
SoftwareSerial gprs(8, 9);
void setup(){
gprs.begin(9600);
Serial.begin(9600);
}
void loop(){
while (gprs.available())
Serial.write(gprs.read());
while (Serial.available())
gprs.write(Serial.read());
}
I later found you should connect it at 115200 baud rate, and if you want to change the baud rate, command it to do so while you are on default baud rate.
AT+IPR=9600 -- to change it
AT&W -- to save the change
and lowering the baud rate is crucial if using software serial.
(the second command should be sent after reconnecting at 9600, since the first command changes the baud rate)
Related
I am trying to get my SIM800C to talk with my Arduino. There is no communication happening, though.
#include <SoftwareSerial.h>
SoftwareSerial at(2, 3);
void setup() {
Serial.begin(9600);
at.begin(9600);
}
void loop() {
// try every 2 seconds
delay(2000);
Serial.println("sending AT ... ");
at.println("AT");
while (at.available() > 0) {
Serial.write(at.read());
}
}
I am not able to get an OK back. SIM800C is supposed to detect the baud rate by itself.
I am sure there has to be a simple stupid mistake. I just don't know what to do at this point. I obviously already checked for cable break. Out of desperation I already tried to switch RX and TX. I also tried different baud rates (whatever is within the usual limitations of SoftwareSerial) but it should automatically detect it once a couple of AT commands got in anyway.
Weird enough, the pin PWX on the SIM800C needs to be hooked up to a GND to work. It started blinking every second now and is responding to AT commands.
Also it turned out that this specific module does not ship with autobauding enabled, as stated by the SIM800C documentation. The correct baud rate is 115200.
There are some problems you need to consider:
Use below sample code which transfers data between PC and SIM. Sometimes SIM module would go into power down state and won't respond on any AT command but would print some results in the serial monitor.
As already mentioned in comments it seems that your wiring is wrong and as you declared Software Serial as SoftwareSerial at(2, 3); which means pin 2 is Rx on Arduino and should connect to Tx pin of SIM and pin 3 is Tx on Arduino and should connect to Rx pin of SIM. Please don't mess with the pins and connect the pins like below correctly.
Arduino SIM
Rx 2 ----> Tx
Tx 3 ----> Rx
I'm not sure if you can power on SIM800 with a 500mA USB connector, make sure that use an external 1/2 A power supply for VCC of SIM module.
Look at the blink speed of SIM module if it connected and powered on it would blinky with 3 seconds delay and if it blinks fast, it means that it is being restarted. Also if SIM powered on correctly it would print some info like SIM READY, CALL READY, etc.
Try other baud rates like 115200 and see if you get anything on power on.
I put some macro definition to make pin mappings more clear.
#include <SoftwareSerial.h>
//SIM800 TX is connected to Arduino D2
#define SIM800_TX_PIN 2
//SIM800 RX is connected to Arduino D3
#define SIM800_RX_PIN 3
//Create software serial object to communicate with SIM800
SoftwareSerial serialSIM800(SIM800_TX_PIN,SIM800_RX_PIN);
void setup() {
//Begin serial comunication with Arduino and Arduino IDE (Serial Monitor)
Serial.begin(9600);
while(!Serial);
//Being serial communication witj Arduino and SIM800
serialSIM800.begin(9600);
delay(1000);
Serial.println("Setup Complete!");
}
void loop() {
//Read SIM800 output (if available) and print it in Arduino IDE Serial Monitor
if(serialSIM800.available()){
Serial.write(serialSIM800.read());
}
//Read Arduino IDE Serial Monitor inputs (if available) and send them to SIM800
if(Serial.available()){
serialSIM800.write(Serial.read());
}
}
Yes this module will not work in this configuration. There is a pin of V_TTL With 5V pin.. This pin enables the TTL logic converter of your GSM.. You have to connect this pin to 5V in case of arduino and to 3V in case of ESP8266.See the pin configuration here
I am trying to run a Processing sketch with my Arduino. I got it a few days ago, so I'm pretty much a noob. I made two similar sketches - one in Arduino and one in Processing. The Arduino one does work, while the Processing sketch doesn't, even though when running the Processing one, the RX lights up on the board.
I have connected an LED into the D9 on the board, with a 220 ohm resistor, and plugged the other leg into the GND. I then proceeded to run the Arduino sketch, which is a simple one, it lights up and down the LED for a second. This one worked.
I then tried running the Processing sketch, exact same code ( adapted for Processing ) using the library for Arduino, and the board seems to communicate with my sketch, as the RX is blinking each second on the board ( I tried different intervals of time and they match with the intervals at which the RX blinks ), but the LED does not turn on and off, like it did with the Arduino sketch.
I tried getting only a serial connection between the Arduino, and it worked - I connected a joystick module to the Arduino and sent the X and Y through the serial port, and the Processing sketch received the information through the serial port, so they are, indeed, communicating.
The port used is COM3 and is running at 9600 baud.
This is the Arduino sketch :
void setup() {
pinMode(9, OUTPUT);
}
void loop() {
digitalWrite(9, HIGH);
delay(1000);
digitalWrite(9, LOW);
delay(1000);
}
and this is the Processing ( version 3.4 ) sketch :
import processing.serial.*;
import cc.arduino.*;
Arduino arduino;
void setup() {
arduino = new Arduino(this, Arduino.list()[0], 9600);
arduino.pinMode(9, Arduino.OUTPUT);
}
void draw() {
arduino.digitalWrite(9, Arduino.HIGH);
delay(1000);
arduino.digitalWrite(9, Arduino.LOW);
delay(1000);
}
Well done on step by step debugging such as double checking the wiring on the electronics side and testing the blink code with the Arduino alone to isolate the issue.
If the Blink sketch is the only Arduino code you have uploaded to your board that won't suffice. Processing does send messages to Arduino (which is why you see the RX LED turn on), but there's nothing in the Arduino code that initialises Serial communication
As you can see in that example, in setup() Serial communication is initialised with 9600 baud rate (communication speed, 9600 bytes/chars per second):
Serial.begin(9600);
Then in draw() if there is data available, each character is read, then printed one at a time with a prefixed message:
// send data only when you receive data:
if (Serial.available() > 0) {
// read the incoming byte:
incomingByte = Serial.read();
// say what you got:
Serial.print("I received: ");
Serial.println(incomingByte, DEC);
}
If you upload the example linked, if you've got a single Serial port, you should see both the RX then ever so slightly after the TX LED blinking when you run your Processing sketch. If you close that sketch, open Serial Monitor in Arduino and type something then press enter you'll see the debugging message read back from Arduino.
Using these notions you could write a basic sketch like so:
int incomingByte = 0; // for incoming serial data
void setup() {
pinMode(9, OUTPUT);
Serial.begin(9600);
}
void loop() {
// send data only when you receive data:
if (Serial.available() > 0) {
// read the incoming byte:
incomingByte = Serial.read();
// say what you got:
Serial.print("I received: ");
Serial.println(incomingByte, DEC);
// if we received ASCII character '1', turn LED on
if(incomingByte == '1'){
digitalWrite(9,HIGH);
}
// if we received ASCII character '0', turn LED off
if(incomingByte == '0'){
digitalWrite(9,LOW);
}
}
}
Uploading this sketch to your Arduino should allow you to type 1 into Serial Monitor and press Enter to turn the LED on or 0 to turn it off.
The only thing left is to send the same data from Processing:
import processing.serial.*;
Serial arduino;
void setup(){
try{
arduino = new Serial(this, Serial.list()[0], 9600);
}catch(Exception e){
println("error connecting to serial port, double chek USB connection, serial port and close other programs using Serial");
e.printStackTrace();
}
}
void draw(){
}
void keyPressed(){
if(key == '1'){
if(arduino != null){
arduino.write('1');
}else{
println("arduino serial connection wasn't initialised");
}
background(255);
}
if(key == '0'){
if(arduino != null){
arduino.write('0');
}else{
println("arduino serial connection wasn't initialised");
}
background(0);
}
}
Minor side note: notice I'm not using delay() in Processing, I recommend using millis() instead as it doesn't block the execution of code like delay() does.
So the above looks like quite a bit of code just to blink an LED but the point is to understand the basics of Serial communication which will be useful on the long run:
initialising serial communication with Arduino (understand baud rate)
basic reading/writing of bytes over Serial
initialising serial communication from Processing and sending data
Back to your original question, you've missed an important detail regarding the Arduino library you're using in Processing: it's relying on a special Arduino sketch (firmware) called Firmata. You will be able to read more on that and how to use the library in this Arduino and Processing tutorial.
As the tutorial mentions you need to first upload this sketch from Arduino > Examples > Firmata > StandardFirmata. Also bare in mind baud rate is set to 57600, not 9600 so you need to update your code like so:
arduino = new Arduino(this, Arduino.list()[0], 57600);
To use: are you sure to put the standardfirmata
Using the Arduino software, upload the StandardFirmata example (located
in Examples > Firmata > StandardFirmata) to your Arduino board.
change the line
arduino = new Arduino(this, Arduino.list()[0], 9600);
to:
arduino = new Arduino(this, "COM3", 57600); // in Firmata -> Firmata.begin(57600);
you could add this line to look after your serial port:
println(Arduino.list());
Modify the "arduino = new Arduino(...)" line below, changing the number in Arduino.list()[0] to the number corresponding to the serial port of your Arduino board. Alternatively, you can replace Arduino.list()[0] with the name of the serial port, in double quotes, e.g. "COM3" on Windows or "/dev/tty.usbmodem621" on Mac.
I got it working with Arduino but I had to change some details. My port was "COM3" or Arduino.list()[1] (the 2nd port on the list) which you can check in Windows device manager (Ports COM & LPT: USB-SERIAL) after installing the latest drivers (maybe on the usb port that appears when you connect your Arduino under other devices) using the system update and restarting, then you may need to repeat the system update and restart 2 or 3 times. Or on Linux, you can find which port it's on with:
ls /dev/ttyUSB*
Then unplug it and check it again.
First I had to upload the Arduino IDE program (running it with the serial monitor window from the tools menu ctrl-shft-m after having the same exact baud rate on the lower right menu option as in the program). Then I could close it and compile the processing one as long as I had input that very same baud rate into the Processing program too. All 3 different bauds that I tried, 9600, 57600, 115200, worked requiring their equality between Arduino IDE, Arduino IDE Serial Monitor and Processing. If I uploaded a different project in IDE, then Processing did not even connect to the Arduino, so it had to be that same project running on it for Processing to communicate with Arduino Uno properly. Processing is basicly USING Arduino IDE by sending or receiving messages already programmed for it to do, it doesn't program the Arduino in this case. I have even gone through a big mess, trying to get Visual Micro to work (Arduino on Visual Studio) cross-platform but it still would not allow me to link other libraries and headers because of how picky Arduino's programming is! One of the best ways to learn is to check the actual arduino.cc or Processing manual command parameters after finding out where your problem is.
I bought a new ESP8266 WIFI module (8pins) and flashed firmware (from https://raw.githubusercontent.com/nodemcu/nodemcu-flasher/master/Win32/Release/ESP8266Flasher.exe) it using arduino Duemilanove correctly.
I have gone through many troubleshooting steps, but on reset module does give some gibberish response, but no Ready/OK response from "AT" command.
Red LED
of module is always on but Blue light is off.
Steps taken :-
To supply enough current i used Beaglebone 3V3 supply as module Vcc.
But i'm not able to receive any response from AT commands.
Arduino Tx (5V) has brought down to 3v3 using voltage divider and
connected to Rx
In Flash settings ensured baud rate was 115200 and all settings correct
Module is working fine presumably as tried with 2 more modules same thing
Here's my connections:
//////////////////////////////////////////////////////////////////////////////
/////// CONNECTIONS ////////
/////////////////////////////////////////////////////////////////////////////
/*
ESP8266 VCC -> BeagleBone 3.3
ESP8266 GND -> Common GND (Arduino & BeagleBone)
ESP8266 CH_PD -> 3K resistor -> VCC
ESP8266 RST -> VCC or pin 13(arduino)
GPIO CAB BE LEFT OPEN OR TIED HIGH
ESP8266 Tx -> pin2 (Arduino software serial Rx)
ESP8266 Rx <- Voltage Divider <- pin3 (Arduino software serial Tx)
*/
Here's my code
#define esp8266 Serial2
#define CH_PD Vcc // but needs a narrow low pulse
#define speed8266 9600 // This is the speed that worked with my ESP8266
void setup()
{
esp8266.begin (speed8266);
Serial.begin(9600);
reset8266(); // Pin CH_PD need a reset before start communication
}
void loop()
{
while(esp8266.available())
{ Serial.write(esp8266.read()); }
while(Serial.available())
{ esp8266.write(Serial.read()); }
}
/*************************************************/
// Reset funtion to accept communication
void reset8266 ()
{
pinMode(CH_PD, OUTPUT);
digitalWrite(CH_PD, LOW);
delay(300);
digitalWrite(CH_PD, HIGH);
}
Here's the output on Serial Monitor
Arduino Serial Monitor Output
Kindly help me what am i doing wrong ?
I don't want to use another FTDI chip while arduino already have it.
At the moment I can only give you a part answer (seems I can't comment yet :) ).
The gibberish is normal when starting/resetting the ESP, it's just the boot code which outputs a boot message at 74880 baud (Which is basically the default baud rate 115200, but because the ESP starts at a lower cpu frequency, the baud rate is also lower, boot frequency is 26 mhz, normal frequency is 40 mhz, 26/40 * 115200 = 74880. If you can set your serial client to 74880 baud you should see the message, but it's an odd baudrate, so it might be hard or impossible to set.
So gibberish on reset is good! It means the ESP is working and happy, the problem is with your software (as you determined yourself too).
I assume your code is on the Arduino side?
The big question is what is flashed on the ESP, and what it's expected bahaviour is. From your question I'm not 100% sure what you did flash on it..
I think you might've flashed nodemcu on it though, which would not respond to AT commands, try to flash the 'original' AT rom from Espressif Systems on it?
I am working on an Arduino-based project. When I send AT commands manually through the serial monitor, I get the correct response, but when I try the same commands through code, the ESP8266 returns garbage values. I've attached both the responses images and also uploaded the program used.
#include <SoftwareSerial.h>
// We'll use a software serial interface to connect to ESP8266
SoftwareSerial ESP8266 (2,3);
//rx=2 connected to 3 of arduino. tx=3 connected to 2 of arduino
const char SSID_ESP[]="xxxxxxxx";
const char SSID_KEY[]="xxxxxxxx";
void setup() {
Serial.begin(115200);
ESP8266.begin(115200);
// Change this to the baudrate used by ESP8266
delay(1000); // Let the module self-initialize
ESP8266.println("AT");
delay(1000);
while (ESP8266.available()) Serial.write(ESP8266.read());
delay(1000);
ESP8266.println("AT+CWJAP");
ESP8266.println(SSID_ESP);
ESP8266.println("\",\"");
ESP8266.println(SSID_KEY);
ESP8266.println("\"\r\n");
delay(1000);
while(ESP8266.available()) Serial.write(ESP8266.read());
delay(2000);
ESP8266.println("AT+CWMODE=3");
delay(1000);
while(ESP8266.available()) Serial.write(ESP8266.read());
delay(1000);
ESP8266.println("AT+CIPMUX=0");
delay(1000);
while(ESP8266.available()) Serial.write(ESP8266.read());
delay(1000);
ESP8266.println("AT+CIPSTART=\"TCP\",\"api.thingspeak.com\",80");
delay(4000);
while (ESP8266.available()) {
Serial.write(ESP8266.read());
}
}
void loop() {}
The Fix
1.
AT commands expect a \r\n at the end of commands. Here you are sending a new line after every part of the command.
ESP8266.println("AT+CWJAP");
ESP8266.println(SSID_ESP);
ESP8266.println("\",\"");
ESP8266.println(SSID_KEY);
ESP8266.println("\"\r\n");
The simple fix would be to change all the ESP8266.println() to ESP8266.write()
2.
Also the syntax for this command has a =" after AT+CWJAP
https://github.com/espressif/ESP8266_AT/wiki/CWJAP
So ESP8266.println("AT+CWJAP"); should be ESP8266.println("AT+CWJAP=\"");
Other Solution
These types of problems can be hard to debug. For this reason I try to avoid sending parts of a command. It would be easier to debug if you use a string.
This also has the benefit of being able to send the command to both serial ports so you can see exactly what gets sent.
String ConnectAPCmd = "AT+CWJAP=\"";
ConnectAPCmd += SSID_ESP;
ConnectAPCmd += "\",\"";
ConnectAPCmd += SSID_KEY;
ConnectAPCmd += "\"";
Serial.println("Sent: " + ConnectAPCmd);
ESP8266.println(ConnectAPCmd);
If you haven't changed it yourself, the ESP8266 dosen't run at baud 115200.
The default is 9600.
Even if the ESP8266 runs at baud 115200, the Arduino dosen't handle 115200 with software serial very well. You might want to change to a lower baud.
That aside I agree with #hlovdal. Use write or print and supply the \r\n to the end of each command e.g.
ESP8266.write("AT+CWJAP=");
ESP8266.write(SSID_ESP);
ESP8266.write(",");
ESP8266.write(SSID_KEY);
ESP8266.write("\r\n");
I think it might be because of low power. Try parallel connecting the power source, for example the Arduino UNO boards 3.3v with a couple of AA batteries to power up the ESP.
This made my ESP8266-01 stop returning garbage characters and also stop disconnecting every now and then.
The problem you are facing is because of baud rate - 115200.
Change the baud rate to 9600 ,it will solve your problem.
I am doing a simple tcp communication from an arduino to raspberry-pi wirelessly with an ESP8266 wifi module on arduino uno.The tcp server is running on the raspberry-pi.I am able to do TCP communication with the following AT commands in arduino serial monitor at a baudrate of 9600.
AT+CIPMUX=1
AT+CIPSTART=4,"TCP","192.168.43.150",7777
AT+CIPSEND=4,5
>hai
How to do this programatically in an arduino sketch.I used the following code on my arduino uno,but still without any success.The baudrate is 9600 only since it is working directly in serial monitor.
#include <SoftwareSerial.h>
SoftwareSerial esp8266(2,3);
void setup()
{
Serial.begin(9600);
esp8266.begin(9600); // your esp's baud rate might be different
}
void loop()
{
esp8266.println("AT");
if(esp8266.available()) // check if the esp is sending a message
{
while(esp8266.available())
{
// The esp has data so display its output to the serial window
char c = esp8266.read(); // read the next character.
Serial.write(c);
}
}
}
The connections are as follows
ESP8266 Arduino Uno
Vcc 3.3V
CH_PD 3.3V
RX RX(PIN 2)
TX TX(PIN 3)
GND GND
This might be a bit late, but I got stuck with a similar problem fairly recently. If it's sorted then feel free to ignore this.
Depending on firmware version of your ESP8266 module the baud rate of 9600 may not work, try out 115200 instead - it may prove to be more reliable?
I think the main reason your code above isn't working is because of the face that the ESP needs both newline and carriage returns at the end of the AT command. The serial monitor adds these on for you. Rather than sending AT try sending AT\r\n. This should encourage the ESP to reply with OK, or if the echo is turned on AT\r\nOK.
Serial.available() also checks that there is content in a receive buffer - this takes time unfortunately so I had to put a delay(10) in there to get it to register a character in the buffer.
#include <SoftwareSerial.h>
//i find that putting them here makes it easier to
//edit it when trying out new things
#define RX_PIN 2
#define TX_PIN 3
#define ESP_BRATE 115200
SoftwareSerial esp8266(RX_PIN, TX_PIN);
void setup()
{
Serial.begin(9600);
esp8266.begin(ESP_BRATE); // I changed this
}
void loop()
{
esp8266.println("AT\r\n"); //the newline and CR added
delay(10); //arbitrary value
if(esp8266.available()) // check if the esp is sending a message
{
while(esp8266.available())
{
// The esp has data so display its output to the serial window
char c = esp8266.read(); // read the next character.
Serial.write(c);
}
}
}
My next problem is that the0 replies for my ESP are unreliable - sometimes they are read as OK but sometime they are garbage values. I suspect it's a matter of not enough power to the module.
I have come across the same problem and yet not have found a solution.
But your connections are a bit of, you have to connect the TX pin of your ESP8266 module to the RX pin of your arduino and the RX pin of your ESP8266 module to the TX pin.
Hope this helps you on your way