XBee cellular LTE Cat 1 sending strange messge at UART port

XBee & XBee Gateway XBee - Cellular
1

my xbee cellular LTE cat 1 chip starts sending message constantly on UART port.

I have a screenshot for that, but I don’t know how to upload it. The HEX content I copied and pasted as following,

41 54 2B 2B 2B 0D
41 54 2B 2B 2B 0D
41 54 2B 2B 2B 0D
41 54 2B 2B 2B 0D
F3 F3 F3 F3 D8 58 58 58 5E F9 5E F9 5E F9 5E F9 6A D3 6A D3 6A D3 6A D3 06 63 E7 06 63 E7 06 63 E7 86 63 E7 20 1E 7A E2 20 1E 7A E2 20 1E 7A E2 20 1E 7A E2 06 06 66 9E 86 9E 86 9E 86 E6 80 06 06 66 9E 86 9E 86 9E 86 E6 80 06 06 66 9E 86 9E 86 9E 86 E6 80 06 06 66 9E 86 9E 86 9E 86 E6 80 78 78 78 78 78 80 F8 78 80 F8 78 80 78 00 78 78 78 78 78 80 F8 78 80 F8 78 80 78 00 78 78 78 78 78 80 F8 78 80 F8 78 80 78 00 78 78 78 78 78 80 F8 78 80 F8 78 80 78 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00 80 00 80 00 80 80 80 80 80 80 00 80 80 80 00 80 80 80 00 80 80 00

I don’t know what is going on here, this board use to work without any problem. Should I consider this as a hardware issue or not? I tried to reset all registers back to default and flash the newest firmware to it. Nothing works.

2

What is the XBee module mounted on? What is it connected to via the UART?

3

The dev kit board, part# XKC-V1T-U, the USB to serial cable connects to the dev board. All that info is shown on the XTCU console working mode panel.

4

Are you using an External power source or just the USB for power?

5

usb power. should I use external and the usb power at same time?

6

This device wants 1A of current or more at 3V. The USB port is not capable of providing that. You must power this device with an external power source using the barrel connector.

7

Is it possible you have some data being sent from a different device to this module?

8

The first sequence of four lines there is the hex representation of “AT+++\r” repeatedly. If you’re already in X-CTU but have the console interface open when it performs operations against the XBee you will see its own data both to and from the XBee.

Color is important, traffic to the XBee will be one color (blue I believe) and from will be another (red). That information is missing from your copied content so it’s harder to figure out what’s going on. I see that you had problems uploading a screenshot, can you restructure the hex data to indicate direction of traffic?

A shot in the dark is that the data after the AT sequence appears to be a set of repeating patterns. It’s certainly not command data. I can think of a couple possibilities to try to rule out:

  1. Somehow you may have captured the X-CTU discovery port scan. The reason this seems possible is because the patterns have a structure that makes it look as if this could be a series of framing errors at various baud rates. Probably being done in a decreasing order because the substring patterns are getting longer, indicating that an increasing number of character frames are being thought to be received.

  2. Are you using transparent mode? If so, this could be data being transmitted from an established connection.

9

yes, we did find a device are sending out that message after a firmware upgrading. Thank you for your help.

10

Yes, the module is receiving that message, not sending those message. we did find a device are sending those message to this module after a firmware upgrading. The problem is on the other device not this one. Thank you for your help.