XTEND-PKG XT09 & XTP9B Dropping Strings

I am sending 3 ASCII strings ending with from one XTEND to one or multiple XTEND modems. Each string is 31 characters or less and they follow one after the other. Periodically, one of these strings gets dropped by a single receiving modem. It’s always an entire string and not just a character or so. I’m also not getting any garbage when a string is dropped as verified using comport toolkit.

In firmware, I am using a network ID and setting the preamble. I also have the transmit power level set to max. My serial Baud rate is 19200 and the RF baud rate is 115200. The remaining parameters are left unchanged.

Are there any additional changes in firmware that would help make this exchange more robust? I believe it may be due to a timing issue causing the modems to not connect during a transmission, but I can’t explain how that makes it drop an entire string. I know there are other XTEND’s broadcasting in the area, but they have different ID’s and Preambles.


I would suggest using user defined mode. Then adjust the RR or MT commands depending on what you are using. This would help increase the reliability of the connection.