Serial interface:

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Components list:
modem/router serial pin: Computer (DB9 female):

  • 1 - Tx
  • 2 - Ground
  • 3 - + 3.3 V.
  • 4 - Ground
  • 5 - Rx
Click to locate serial on modem PCB  
  • 1 - Rx (2)
  • 2 - Tx (3)
  • 3 - Ground (5)
  • Join 1 + 4 + 6 e 7 + 8