Page Comparison

use breakpoints and figure out what your raw message looks like. Compare with this guide to ensure that its in order. Check the length value and the checksum value. IF THE CHECKSUM IS WRONG YOU WONT SEE ANYTHING ON THE RECEIVER SIDE. Use the XCTU frame builder and recreate your message, it'll calculate a length and checksum for you, to compare with the actual frame being sent (if there is something wrong with your frame this will expose that).
use an oscilloscope to read the uart signals on the sending and receiving end. You want to ensure that there is a good signal going to the sender, a good response (no error codes) from the sender to the stm32, and then the receiver sees the message.

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XCTU

XCTU is software that we can use to configure and run the xbees. We first used this software to send some test frames using the zigbee 3.0 protocol. This tool can be used to generate frames (and you can compare checksums/frames with the ones your program is generating.

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Logic Analyzer

Worst Case Scenario: you can always use a logic analyzer to read the exact data the xbee is sending/recieving, although this is painful to do.

Python:

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Overview

Inventory

Name	Address	Freq	Antenna	range (LOS)	range (urban)	data rate
Xbee Pro S3B	0013A20040B47E80	928 MHz	dipole	14 km	610 m	160 kbps
Xbee Pro S1	0013A20040B0EC97	2.4 GHz	dipole	x	x
Xbee Pro s1	0013a20040b0ec69	2.4 GHz	dipole	x	x
xbee pro s3b	0013a20040b47e6b	928 MHz	dipole	14 km	610 m	160 kbps
xbee pro s3b	0013a20040e47deb	928 MHz	dipole	14 km	610 m	160 kbps
xbee pro 900	0013a20040674c02	900 MHz	integrated wire	x	x	156 kbps
xbee pro s3b	0013a20040e501f1	928 MHz	dipole	14 km	610 m	160 kbps
xbee pro s3b	0013a20040e501e1	928 MHz	dipole	14 km	610 m	160 kbps
xbee pro 900	0013a20040789b2b	900 MHz	dipole	14 km	610 m	156 kbps
xbee s2c	0013a20041c0f315	2.4 GHz	small antenna	90 m	30 m
xbee s2c	0013a20041c0f209	2.4 GHz	small antenna	90 m	30 m

We also have 5 uart to usb xbee boards, and 3 dipole antennas.