turn off active time and go directly to power save mode

RE: turn off active time and go directly to power save mode

visu — Fri, 22 Nov 2019 09:26:20 GMT

Hi Martin,

set active time to "0000000" worked well! didn't realize that I could solve it in that simple way... thanks for your help!

RE: turn off active time and go directly to power save mode

Martin Lesund — Wed, 20 Nov 2019 16:05:22 GMT

Hi Visu,

When setting the active time I think it is best to set it to "0000000" instead of "1110000" if you want it to be zero.
I do not think "1110000" is valid to request but instead is used as a response from the network that the timer is deactivated.

e.g

AT+CPSMS=1,"","","10101010","00000000"

periodic tau= 10min

active time = 0 second

Remember that some networks can have a longer RRC Connected release period than others. Which impacts the time from going from RRC Connected to PSM mode.

RE: turn off active time and go directly to power save mode

visu — Wed, 20 Nov 2019 11:51:40 GMT

Hi Martin,

for CPSMS i set: AT+CPSMS=1,"","","00100001","11100000"

and the response in XMONITOR is:
answ: %XMONITOR: 1,"","","22801","0E10",9,20,"0100CED0",279,6290,77,37,"","11100000","11100000"

I am using a local SIM and NB-IoT. PSM mode should be supported. If I try with 32 secs active-time, the nrf9160 goes in psm after the 32 seconds.

I am using a power analyzer so I can see whether the nrf9160 is in connected state, idle state or psm

RE: turn off active time and go directly to power save mode

Martin Lesund — Wed, 20 Nov 2019 09:33:48 GMT

Hi Visu,

Could you share the response from the XMONITOR command?

How do you know you aren't going into PSM mode?

Are you using a local SIM? Which network? LTE-M or NB-IoT? Could you confirm that this network supports PSM mode?

Best regards,

Martin L.

RE: turn off active time and go directly to power save mode

visu — Tue, 19 Nov 2019 16:17:15 GMT

Hi Martin,

Thanks for your quick reply. Of course it is 15min, that was my fault.
I read out the values with XMONITOR, which should be the same with CEREG and i get the value 11100000 for active time, but the nrf9160 does not get into power save mode

RE: turn off active time and go directly to power save mode

Martin Lesund — Tue, 19 Nov 2019 14:49:30 GMT

Hello Visu,

The +CPMS command sets the requested periodic TAU and requested active time, the network decides if it will approve these requests or not.

You can read out the values given from the network with the command AT+CEREG?.

You have requested a Periodic-TAU of "10101111" which is 15 minutes according to Table 10.5.163a/3GPP TS 24.008.

You have requested an Active time of "11100000" which indicates that the timer is deactivated according to Table 10.5.163a/3GPP TS 24.008.

Also, a good idea is to hook up a power analyzer to the device so you could actually see that you go into PSM mode.

What should be mentioned is that we see that usually that networks do not allow roaming SIM cards the PSM feature.
So please test out with a local SIM card.

Best regards,

Martin L.