This command is exactly same as the CTU, CTD command, except this command will be able to remember its count when the module is powered off. By comparison, the CTU,CTD command will lose its count when the module is powered off.
This command can only be used with modules that support battery backup such as the CB290, CB405, CB405RT and CT1721C.
When using this command for the very first time, use the RESET signal to initialize the counter. Otherwise the counter could start at some random value.