Modul GSM SIM800L and two board

Hello,
I have a GSM GPRS modul SIM800L.

Is it possible to connect two Arduino Board to parallel connection?

My tests say no…

  • when I connect Arduino bord No1 to Modul, all is OK
  • when I connect Arduino bord No2 to Modul, all is OK
  • when I connect No1 and No2 parallel to modul, modul GSM does not communicate…

I am not sure why… Is my idea right?

Thank

Hi,

so I found solution myself :slight_smile:

The problem: you can not connect pins Output on the board No1 with pins Output on the board No2!

Solution: You have to connect between pins the diode, so after the paralel connection works well.