Can't wakeup Dragino LA66 USB from sleep

End Devices (Nodes)
1

Hello Guys,

I know this isn’t the right place to ask, but since I didn’t find another solution…

I did put my LA66-USB (v1.1 EU868) into sleep mode with the AT+SLEEP command
When asking for the status:

AT+SLEEP=?
1
OK

Does anyone know which AT command to use to wake it up?

Thanks in advance
Michel

2

How do you mean? The topic you’ve chosen or that we aren’t the Dragino forum?

Does it not wake when you send another command? Most AT modules do that!

3

Hello Nick,

How do you mean? The topic you’ve chosen or that we aren’t the Dragino forum?

This isn’t indeed the Dragino forum…, So I thought none real TTN stuff is not done…

Does it not wake when you send another command? Most AT modules do that!

No it doesn’t:

Check Sleep Mode, 0 is not sleeping

AT+SLEEP=?
0
OK

Put in Sleep Mode

AT+SLEEP
SLEEP
OK

Check Sleep Mode, 1 is sleeping

AT+SLEEP=?
1
OK

Send another command (check version)

AT+VER=?
EU868 v1.1
OK

Check Sleep Mode, 1 is still sleeping

AT+SLEEP=?
1
OK

Thanks for thinking with me.
Michel

4

Huh??

This is a bit meta, but it can’t really report that it’s asleep if it’s able to respond to AT commands and/or then go on to check version.

Unless the meaning is that it is happy to sleep if not being asked questions.

The way to check is put a multimeter on mA’s and see what happens - it’s unlikely to show a meaningful value when it’s asleep so you should see it running a few mA when you interact and then possibly drop to zero when you tell it to sleep &/or leave it alone for a few minutes.

5

The way to check is put a multimeter on mA’s and see what happens - it’s unlikely to show a meaningful value when it’s asleep so you should see it running a few mA when you interact and then possibly drop to zero when you tell it to sleep &/or leave it alone for a few minutes.

I will do that, but since it is the USB version (with USB A connector) and plugs directly into my PC (running MicroRidge ComTestSerial) I will first have to make a “man in the middle” USB cable for connecting the amp meter.

I also did send a mail to Dragino Support, Just waiting for their answer.

Greetings,
Michel

6

Have you tried AT+SLEEP=0 as a command?

7

Hello Jac,

Yes tried (and many other look a likes), that gives an at command error

Michel

8

Interestingly the source code does have a function where it sets the value ‘sleep’ value to 1, but (according to GitHub search) none where it resets the value.
Given the amount of timers the get canceled my guess is that you need to issue the reset command (ATZ) to get the module operational again, too much of the stack has been shutdown to recover cleanly.

9

Hello All,

First of all, thanks for helping me solving this problem.

This is the answer I did get from support@dragino.com:

This command is only a setting for nodes that need to use batteries
LA66 USB does not need this command

A bit strange answer, why shouldn’t USB based devices not be put into sleep to save power between transmissions?

Thanks,
Michel

10

My guess: this is a command they issue after programming a battery powered device in the factory to make it sleep until the new owner presses the button to wake it up. It makes sure the device goes inactive and doesn’t try to transmit (or receive) wasting valuable milliamps from the battery,

Normally the device should be consuming very little anyway when not transmitting/receiving/measuring a sensor value. Should be in the order of micro amps. (The USB powered device might well be an exception and use more because there is more power available)