Different definitions of parameter periodic-tau in at instruction CPSMS and XMONITOR

[duxinglang]

I am using 9160 to develop a watch product. During the network test, I found that the description of parameter period tau in CPSMS instruction and xmonitor instruction is different. I want to know which description is correct? Although I know that CPSMS is defined by the terminal by default, xmonitor is obtained by the network.

[Hakon]

Hello,

I want to know which description is correct?

They are both correct. But they are not the same thing. The first one is requested periodic-TAU, being requested by the application, whereas the second one is the periodic-TAU set by the network.

[duxinglang]

If so, then I have another question, since the network can only give these four types of TAU time, why can the application request for so many time types?  Is it not effective to apply for tau time that the network cannot support?  

[Hakon]

duxinglang said:

why can the application request for so many time types?

The network can also assign an extended periodic TAU value as indicated in the XMONITOR documentation. This corresponds to the range of the CPSMS values.

[duxinglang]

Which brings us back to the question, is it the tau that's doing the work or is it the extended tau that's doing the work?  At what time does the modem finally start to interact with the base station?

[Hakon]

duxinglang said:

At what time does the modem finally start to interact with the base station?

What do you mean by this? Are you asking how often the device interacts while in PSM? This should be after the periodic-TAU, unless the application tries to send any data.