HL7812 GPIO2 constantly ON while in PSM mode

IoT Modules HL78
1

Hi,

I am using the HL7812 with the latest 5.5.14.0 firmware. I have configured the GPIO2 with at+ksync=2,2

When in PSM mode the GPIO2 is always high which is obviously wrong.

The same procedure but with the HL7800 with latest 4.7.1.1 firmware does not have the same issue and the GPIO2 goes low.

Is that a known bug for the HL7812?

thanks

2

How do you know it is in psm mode?

3

PSM is working fine on HL7800 modems with current draw at 100uA as it should:

4

Then what is the current for the hl7812?

Did you also check VGPIO pin?

5

Current is 20mA but I do get +CREG: 0,4 indicating that PSM mode has been entered.

And upon waking the modem up, +CREG: 0,5 happens immediately, indicating that the modem was indeed in PSM mode.

VGPIO is always high unlike the HL7800 where it goes low after +CREG: 0,4.

thanks

6

seems the current consumption is not matching with PTS:

image
image1034×466 70.8 KB

7

Right. So my question still stands.

With the exact same procedure in the HL7800 the PSM works fine but in the HL7812 it does not.

Has the PSM been tested with the HL7812, or is there some known workaround that needs to be followed?

I’ll keep testing this and will get back to you if I find the culrpit.

thanks

8

if you compare VGPIO, it works in HL7800 but not in your case in HL7812.
It seems that the module is not in PSM mode according to the current consumption

Did you set the same for AT+KSLEEP between the case in HL7800 and that in HL7812?

9

Yes everything is done the same. So you are right in that it does not enter PSM mode or at least something is going wrong.

10

you can see the application note which covers HL7812: