How does the XB module to talk to ESP board in AWS Gateway?

Hardware
1

Hi,

I just got a new AWS Gateway this afternoon.

I would like to directly drive data into the XBee socket interface instead of reading from LPWA-connected sensors for initial testing and development.

Is this possible?

If so, how is the XBee communicating to the ESP module?

Thanks!
Jason

2

Hi Jason,

Yes, it’s possible, although I would not say it is simple. I assume you’ll be pulling the XBee module out of the gateway and directly applying data from another device in place of the XBee. All data comes in through the XBee socket Rx/Tx lines. Google XBee pinout and you can find where those connections are. Keep in mind you also need to connect to the GND pin to send RS 232 data to the XBee socket. We utilize the DigiMesh protocol on the XBee module. You’ll need to look up the documentation for the 900HP Digi module and find the section on Receive packet. This packet structure will need to be replicated by your “spoof” device. Also you’ll need to replicate the payload generated by our wireless sensors which is documented on the product pages under resources.

3

Hi Travis,

Thank you very much. This is excellent information.

Let me see if I interpreted your feedback correctly:

  • UART hardware connection between XBee and ESP32 module
  • DigiMesh protocol, Receive Packet specifically (as defined by DIGI)
  • NCD payload structure (defined by NCD)

Is this correct?

Thanks!
Jason

4

Hi Jason,

Yes, that is correct. Let me know if you run into any questions.

5

Thanks for confirming.

Can you point me to a specific URL for the payload description?

Thanks!
Jason

6

Never mind. I have looked at the manuals for a few sensors, and I see where the payload description lives.

Thanks!
Jason

7

Yeah, look at the run mode section of the sensor product manuals and you should find what you need.

8

Yes, I started with the Push Notification sensor to keep things simple. :slight_smile:

What baud rate is used between the XBee and ESP32 board?

Jason

9

Baud rate is 115200. Sorry I forgot to mention that. Sort of important :wink:

1 Like
10

Thanks Travis.

I posted another thread related to my gateway dropping connection, and I depending upon your answer to the follow-up question I provided, I may need to add some additional smarts to my driver.

Is there a start-up sequence I would need to send to the ESP32 from the XBee driver before I start sending packet data?