Forcing N211 into Power Save Mode (PSM)

1

Hi guys,

I have managed to get my N211 NB-IoT Shield into PSM after sending a message using the AT+NSOSTF command. The entire shield draws about 60uA, which seems fine. The N211 should only draw 3uA, but I guess there’s some pullups/pulldowns on the shield that leak some current. I’m currently in the process of determining the real sleep mode current using a N211 EVK.
But, I don’t want to send a message to get the N211 into sleep mode. Is there any other way of forcing the N211 into sleep mode? I was not able to find any commands that do so.

AT+CPSMS is used to enable the PSM and set the timers.
AT+NPSMR enabled the PSM URC’s.

I’ve seen this in a datasheet:

So I’d say the N211 would just go into PSM if it doesn;t get any AT inputs (if PSM if enabled ofcourse), but it doesn’t. It draws about 40-60mA.

My settings are: +CPSMS: 1,“01000001”,“00000101”
This should mean it will go into PSM after 5 x x 2s = 10s. Yet it doesn’t.

My R410M had a AT+CPWROFF command that I could use, the N211 doesn;t seem to have a similar command.

I haven’t found any command to directly put the N211 into PSM. I’m probably missing something, this must be doable right?

~Michael

2

Dear @M.Bend,

The N211 indeed does not have a command to put it into PSM.
The N211 module will when it is inactive automatically go into PSM when enabled.

I believe after settings the PSM, you have to turn off and on the radio. Then the settings are applied.
Or after sending a message. I don’t have a board here atm to check it.

In our use cases we always send a bootup message to know when a device has been reset.

Best regards,
Jan