HL7812 + HL78 Dev Kit Low Power Modes

IoT Modules HL78
1

Hi all,

I am using the HL7812 IoT module in the HL78xx Development Kit but I am unable to force it into a low power mode using the +KSLEEP command. I have tried setting the module up in both the PSM Use Case and the eDRX Use Case outlined in the HL7800 Low Power Mode Application Note but I am not seeing the current consumption drop at all to indicate sleep. Are there other conditions that are required to enter sleep or hibernate?

I am measuring the global current consumed by the module (baseband + rf) as per the HL78xx Development Kit User Guide i.e. measuring the current through header CN804.

Thanks in advance.

2

Hi connor,

Did your HL7812 register to CatM1 or NB1 network?

Could you provide the AT commands you used in detail?

Thanks,

3

Hi jerdung,

Registering to CatM1 network.

After turn on I send:

AT+KSLEEP=1,1,0
AT+CPSMS=1,“00100001”,“00001111” // TAU = 1hr, active = 30 seconds

And that’s all I am doing at the moment. During PSM active time registration status is +CEREG: 1, during TAU time registration status is +CEREG: 4. As far as I understand this is correct.

Thanks.

4

Hi connor,

You should use CPSMS command before KSLEEP command. Also, check and turn off the WAKE-UP pushbutton on your devkit.

Thanks,

5

Hi,

I have changed the order of the AT commands as you suggested and the WAKE-UP switch is off. I have noticed the FAST_SHD LED is continuously illuminated even though the button is not being pressed.

Result is the same. I am measuring ~14mA when the module should be in lite-hibernate mode.

Thanks.

6

Hi connor,

HL7812 has not been officially sold yet and there is no official firmware on Sierra source page. I don’t know if the LPM feature worked well on this product. Could you please contact the supplier of this product for the info?

Thanks,

7

Hi jerdung,

Yes I can do that. Thanks for your help :slight_smile: