The Arduino does not execute commands when I unplug the Arduino.. It only executes commands when I press the restart button

Thanks for watching.. I am using an Arduino Nano with SIM800L module to send and receive messages and commands are executed correctly.. In the design I am using an external power supply to the Arduino via a battery.. When the battery is disconnected by the switch, the power to the Arduino is disconnected here when I Turning it on again the arduino only works by pressing the restart button.. I want a solution to this problem I want when I unplug the power from the Arduino and then plug it in it executes the code without pressing the restart button every time
I don't know the programming code is necessary to download it or not. If necessary, I will upload it

The Arduino doesn't reset, or the GPRS board doesn't reset? Try unplugging the shield, load the blink sketch and see if it resets and blinks...

I think that we're missing some details. Any Arduino will reset if you remove and re-apply the power.

  1. Which Arduino are you talking about?
  2. Which SMS module / shield are you using?
  3. By unplugging, do you mean disconnect from the PC?
  4. How do you power the Arduino? Via USB? Or with and external power supply? If the latter, what exactly.

Your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advise on) your project :wink: See About the Installation & Troubleshooting category.

Thanks for watching.. I am using an Arduino Nano with SIM800L module to send and receive messages and commands are executed correctly.. In the design I am using an external power supply for the Arduino via a battery.. When the battery is disconnected by the switch, the power to the Arduino is disconnected here when I Turning it on again the arduino only works by pressing the restart button.. I want a solution to this problem I want when I unplug the power from the Arduino and then plug it in it executes the code without pressing the restart button every time

This is confusing. Please explain exactly how the Arduino and module are connected and powered

Thank you for your help.. I am using a 12V power supply to power the Arduino Nano and I am using Step Down 3A to power the SIM800L. The connection between Arduino and SIM800L is TX and RX only. The board is fully operational. I sent a message to turn on the LED. The board received the message and turned on the LED.. but for the source, when I unplug the power and then turn it back on again. The code only works when the restart button is pressed.. The programming code does not work after turning off the power and it turns on only when the restart button is pressed.. I want to solve this problem when the power is off and then turn it on. I want the program to be executed without pressing the restart button.
Thank you, can I send you more details?

Are you giving enough time for the SIM800L module to properly start up?

Is there also a common GND connection between the two ?

Which pins are you using to communicate between the Arduino and the module ?

Please post your full sketch, using code tags when you do

Yes, wait until it is fully connected to the network

Earth yes connected to each other I will now send you the diagram

Are you sure that also happens when power has been cut off completely?

This problem only appears when the power is off and then plugged in again. Arduino only works by pressing the restart button.. yesterday I switched the Arduino but there is the same problem

Please post your full sketch, using code tags when you do

Thank you.. I did what you said but it seems the same problem I have to reset the Arduino

finel___prog___with_arduino.ino (‏9.1 ‏ك.ب)

Now I did another experiment. I've taken the Arduino off the board and tried it off the board. The operation worked correctly, but when I put it on the board, it doesn't work it asked me to restart

Please make it easy to help you and post the code here following the advice to use code tags in How to get the best out of this forum

All it takes is 2 mouse clicks

I don't see any PWRKEY or STATUS signals in your schematic. How is the power on/off sequence handled? Is there something built into the module you're using?

Look at the board from the top there it says a switch in this place I connected a switch and disconnected and connected the Arduino.. the switch is only connected to the ground line is this a problem or what should I cut off the positive and negative lines
Thank you very much for the help