How do you get PSM to work on the R410M?

Hi guys,

I’m currently trying to get PSM to work on the R410M but without succes. Is there anyone who has got PSM to work and could send me the AT command sequence that did the trick?

Hi @NielsVeul,

This command should be the only thing you need I think:

AT+CPSMS=1,“01000011”,“01000011”.

You can adjust the settings according to what you want. You can view the settings in the AT commands manual 14.7.

The R410 Should go into PSM automatically if it doesn’t have anything to do.

I’m not 100% sure this works, I’m currently working with the N211 myself, which works a little bit different.

Reading all the available datasheets has helped me a lot.

Good luck!

~Michael

Hi Michael,

Thank you for the reply. I tried AT+CPSMS, but the modem won’t go into power saving mode. Therefore I was thinking I might have missed some additional settings.

It will only go into PSM when it doesn’t have something to do. The AT command won’t force it into PSM. I use a sequence that connects to the network and sends a message. After the message is sent it will go into PSM.

I managed to put the modem into PSM but it won’t wake.
This are the settings I used: +CPSMS:1,“01111110”,“00000111”.
From my understanding this means the modem should wake after one minute of PSM?

It will wake up to see if it gets any messages from the server. If it doesn’t it’ll go back into sleep mode. Waking it up yourself can be as simple as sending an AT command to it. You only use the 2nd PSM timer to wake it up just to check if your server wants to send any data. In my case, I’ll only be sending data, not receiving it, so I don’t have to bother with the 2nd timer.

Hope that clears things up. Good luck!

~Michael

This clears it up Michael, thank you, I will also only be sending data.

I managed to get PSM working but I don’t really see the point of using it. My modem takes just as long to wake from PSM, as it takes to wake from complete power off. Therefore, cutting off the supply from the modem is better for the battery life.

If it is possible to decrease the startup time from PSM, that would be great.

The upside of using PSM is that your can instantly send data again. Cutting of power means you will need to connect to the network again. I’m currently doing some calculations wether PSM or cutting off the power is more efficient.

Booting, connecting and sending some data takes about 650mAs for me.
Just sending the message takes about 80mAs. Assuming 4uA sleep current that draws 345,6mAs per day.

This means you can send 3 messages if you stay in PSM compared to sending 1 message when cutting of the power.

Hope this helps!

Note: this data is for the N211. Which is a bit more efficient that the R410. But I kinda assume having the R410 in PSM will still be more efficient.

Thank you for the data. I ran the test of booting and sending a message myself and got similar results.
The problem with PSM on my R410M is that it won’t respond to AT commands while in PSM, so I’m not able to send messages without waking it up by toggeling the startup pin.

I’m hoping someone can help me to get PSM to work, with the modem still responding to AT commands.

Hmm, that’s odd. My N211 simply wakes up when I send any AT command. I figured the R410 would do the same, I guess not.
I hope somebody has had a similar issue, good luck!

Small update on the issue,

It has been brought to my attention that the R410M has a different chipset than the N211, since it supports LTE-M as well. In this chipset the only thing that is awake during PSM is the RTC, so it won’t be able to receive any AT commands. The only way to wake the modem from PSM is toggeling the power on pin just as if the modem is completely powered off.

As a result, waking the modem from PSM takes just as long as waking from power off. Therefore, I don’t see the point in using PSM on the R410M, since the only thing that it seems to do is increase the power consumption compared to a complete power off, without offering any obvious benefits.

Good to know, very odd thought. Thanks for letting us know. I started out using the R410 myself too, but switched to the N211, kinda glad I did now :slight_smile:

Good luck!

~Michael