XBEE seems to be unresponsive

Wireless & IoT Other Radios
1

Hi,

this is a crosspost:

I have a XBEE 3 Micro (XB3-24Z8CM Rev C) soldered on a custom PCB. The Xbee is connected to an Teensy 3.2.

I can’t connect to it via serial connection. I am using ‘+++’ to get into AT mode, but get no answer.

My serial seetings are 8n1 at 9600 Bauds/s.

I made the following connections:

GND to Teensy GND

VCC to Teensy 3v3

DOUT to Teensy RX

DIN to Teensy TX

Using an oscilloscope, i get the following signals on the pins:

1.GND) 0V

2.Vcc) +3v3

3.DOUT) 0V

4.DIN) my serial signal (‘+++’)

  1. +3v3

6.RESET) +3v3

7->19) 0V

20.RSVD) +3v3

22->34) 0V

I’m especially surprised that I’m getting 0V on the ON-pin.

What am I doing wrong?

2

Use a multimeter in resistance mode to check if there is a conduction path to GND. Unless it is set as a DIO13 (which I don’t know how to) it should be high by default unless transmitting.

3

I measured 5.6k from DOUT to GND.

Is there a way to check if my module is electrically broken?

4

Unsolder the device from the custom pcb and test again. Without knowing what you PCB is like and contains as other circuitry it is impossible to suggest alternate causes of this.