Campbell Scientific SDM-IO16 16-Channel Input/Output Expansion Module - Manual (Page 4)

2. CR23X and CR10X Operating System
Requirements
Use of SDM-IO16 Instruction 188 requires newer datalogger
operating systems for the CR23X and CR10X.
NOTE
The following table lists the datalogger operating systems required for support
of Instruction 188. To determine which operating system is presently installed
in a datalogger, use the *B mode. See your datalogger manual for a detailed
description.
Campbell Scientific
Datalogger
Required Operating System Version
--Listed version or later--
CR10X 1.17
CR23X 1.14
Campbell Scientific datalogger operating systems are easily downloaded from
our website page, www.campbellsci.com/resource.html. Go to section Product
Upgrades and click on the link for the appropriate datalogger.