SIM 800L cannot connect to at - arduino

I am trying to send some data using the sim800l module.
I am using the SoftwareSerial library and connected the RX and TX pins to Digital pins 10 and 11. I have also tried pins 2 and 3.
The module is connected to a 5v power supply and the only pins connected to the Arduino board are RX and TX.
The module is connected to the network.
this is the code I am using:
#include <SoftwareSerial.h>
SoftwareSerial myGsm(10,11);
void setup()
{
myGsm.begin(9600);
Serial.begin(9600);
delay(500);
myGsm.println("AT+CGATT=1");
delay(200);
printSerialData();
myGsm.println("AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"");//setting the SAPBR,connection type is GPRS
delay(1000);
printSerialData();
myGsm.println("AT+SAPBR=3,1,\"APN\",\"\"");//setting the APN,2nd parameter empty works for all networks
delay(5000);
printSerialData();
The problem is that nothing gets printed in the serial monitor.
I used the module to send sms messages using the FONA library and it worked.
Please help!

I think the problem is,
To print something on the serial monitor, you need to use the Serial.println();
The softwareSerial println only sends data to the devices connected to that pins.

Related

AT-Commands from ESP32 to Fanstel BC805M (nRF52805M) not working

I want to send a simple AT-Command like: AT\r\n from the ESP32 to the Fanstel BC805M (nRF52805M) breakout board. My goal is to get an answer.
Problem: The Esp32 does not get an answer from the BC805M.
Setup
Hardware
The ESP32 is connected by usb cable to my Mac.
The ESP32 connects to the BC805M by five cables -> 3V3->VDD, GND->GND, Rx->Tx, Tx->Rx, GPIO32(high)->GPIO04(P004). Rx and Tx from ESP32 are Serial2 (not the Serial0 of the programmer). The P004 pin from BC805M is set to high to enable "command-mode".
Software
The BC805M came already preloaded with The AT commands code.
The ESP32 is flashed by a simple Serial2 write/read arduino code:
#include <HardwareSerial.h>
#define RXD2 16
#define TXD2 17
#define CMD_MODE 32
void setup() {
Serial.begin(115200);
Serial2.begin(115200, SERIAL_8N1, RXD2, TXD2);
pinMode(CMD_MODE, OUTPUT);
digitalWrite(CMD_MODE, HIGH);
delay(1000);
Serial.println("start");
}
void loop() {
Serial2.write("AT\r\n");
delay(500);
if(Serial2.available()){
Serial.write(Serial2.read());
}
}
On Monitor, I received nothing: Terminal Output
What I tested
I connected the two ESP32 Rx and Tx Serial2 Pins with each other and the monitor prints AT AT AT ... (so this works)
I connected the ESP32 with the BC805M not by crossing Tx and Rx but like: Rx->Rx, Tx->Tx; I received the message
BlueNor 200622 started
on my monitor. This means I read the values of the Rx pin of the BC805M and wrote them to my monitor. Shouldn't this message be sent on on the Tx pin of the BC805M?
I connected to the BC805M per Android App, which connects to it via Bluetooth Low Energy. I sent commands from the app to the BC805M. But I got no response. I could read the commands I sent on the Rx Pin of the BC805M.
I connected solely the BC805M per usb to my mac and ran Arduino-IDE's monitor, the monitor prints absolutely nothing and writing AT-Commands also results into nothing.
The Fanstel support just wrote me that the BC805M Evaluation Board is NOT preloaded with the AT-Command firmware.
Only the BC805M module has it preloaded.
That explains why the AT-Commands did not work.

Arduino Nano no serial communication SIM800C

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

SIM800L Cant Send Message

I have a SIM800L module.
I have configured my 800L SIM module, where I connect OUT+ on LM2596 to VCC on SIM800L and OUT- on LM2596 to GND on SIM800L. Besides that, I connect TX SIM800L to pin 2 Arduino and RX SIM800L to pin 3 Arduino
Then, After the source code is uploaded to the arduino mega 2560 board, the SIM800L module flashes 3 times every 3 seconds, sometimes also blinks 7 times every 3 seconds. So on.
And until now my SIM800L module cannot send messages. where is the problem? thanks please answered
First, you must double check that the modem is connected correctly and have enough power. To ensure that I always try to read the output serial of the modem in startup and make a call to it.
If modem starts correctly it should print some data in the serial output (with default settings) and some of them prints the power issues.
You can use the following example to creating a two-way communication between your host PC and the modem. In here I'm using Serial1 with pins 18, 19.
If I remember correctly the blinks should be every 3 seconds, and if it changes it means that modem is being restarted.
After that, you can send AT commands with your host PC and check the functions.
#include <SoftwareSerial.h>
#define serialSIM800 Serial1
void setup()
{
//Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
Serial.begin(9600);
//wait on host serial
while (!Serial);
//Being serial communication with Arduino and SIM800
// you should double check the default baudrate of SIM800 and set it here
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());
}
}

SoftSerial Not Working ESP8266

I am trying to communicate with my ESP8266 module through Arduino Mega with the ESP's Rx pin connected to Mega's Pin 7 the ESP's Tx pin connected to Mega's Pin 6. I tried to run the following test code:
#include <SoftwareSerial.h>
SoftwareSerial esp8266(6, 7);
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(115200);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
Serial.println("Started");
// set the data rate for the SoftwareSerial port
esp8266.begin(9600);
esp8266.write("AT\r\n");
}
void loop() {
if (esp8266.available()) {
Serial.write(esp8266.read());
}
if (Serial.available()) {
esp8266.write(Serial.read());
}
}
I get no response from the ESP8266 module. I then tried to use the Mega's dedicated Tx and Rx pins (1 and 0 respectively). I can send commands using the serial monitor and it replies. First I sent AT+CIOBAUD=9600 under a 115200 baud to change the baud rate of my ESP module to 9600. Then under 9600 baud I sent AT+UART_DEF=9600,8,1,0,0. It replied OK for both as expected. I tried again to run this program but I'm still getting no response from the ESP 8266 module. I also tried simply switching the Rx and Tx pins just to be safe. Still doesn't work. Any ideas on what I might be doing incorrectly?
As you've mentioned in comments, SoftwareSerial esp(6,7) works on UNO but not on Mega. That should be hint big enough to google the Arduino SoftwareSerial reference page, particularly the Limitation section.
In short, unlike UNO the Mega doesn't have Pin Change Interrupt capability on all pins. So you can't have Rx pin on pin 6.

How do I fix HM-10 BLE module from returning odd characters?

I am trying to send data to an Arduino via a HM-10 module(BLE) from a MacOS device and am following this guide. For my wiring, I have done the following: I have the RX pin on the HM-10 hooked to the TX on the Arduino; the TX pin on the HM-10 to the RX on the Arduino; the VCC on the HM-10 to the 3.3V on the Arduino; the GND on the HM-10 to the GND on the Arduino.
I am using the following code:
#include <SoftwareSerial.h>
SoftwareSerial BTSerial(0, 1); //RX|TX
void setup(){
Serial.begin(9600);
BTSerial.begin(9600); // default baud rate
Serial.println("AT commands: ");
}
void loop(){
//Read from the HM-10 and print in Serial Moniter
if(BTSerial.available()) {
Serial.write(BTSerial.read());
}
//Read from the Serial Moniter and print to the HM-10
if(Serial.available()) {
BTSerial.write(Serial.read());
}
}
When I send AT+NAME?, I should be receiving OK+NAME:HMSoft, but I keep on getting a string of odd characters: AV⸮5⸮. In addition, none of the commands seem to have any effect.
What am I doing wrong that I am unable to interact with the HM-10 from my computer?
SoftwareSerial BTSerial(0, 1); //RX|TX
You are using hardware serial pins for software serial. And you are then using both, which corrupts the data.
Move the software serial pins to different ones, like 2 and 3.
After changing the pins to 2 and 3, choose Both NL&CR option to send commands to Arduino through the IDE. Otherwise it's not going to work.

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