WH-LTE-7S1 GSM module and SIM card problem

[setbit]

Hi all!
I can communicate with the WH-LTE-7S1-E LTE/GSM module, but it sends periodically "No SIM<CR><LF>" messages and "WH-LTE-7S1-E" boot messages. These messages are disturb my communication. Of course, I put SIM card into the socket.

Both of SIM cards I tried, are valid, and works perfectly in other devices from 1.8V power voltage.
I see SIM DAT and SIM CLK activity before No SIM<CR><LF> messages. The signal shapes are correct.
The SIM RST pin goes to 1,8V 3,8sec after power on.
I pulled up the SIM_DAT pin to 1.8V VSIM voltage, (as WH-LTE-7S1-E Hardware Manual suggests) but it doesn’t helped.
A strange thing I see, the SIM CLK has 32 period on the shortest (probably 1 bit wide) SIM DAT pulse.
Unfortunately there is nothing info on the internet about usage of WH-LTE-7S1-E.
The factory documents are not very talkative, and I can not found any application or a row of source code about this module.
Link to factory documents: https://www.pusr.com/products/LTE-Cat-1-module.html

Any ideas are greatly appreciated!
Gyuri

 

[FvM]

Periodic reboot suggests insufficient peak current capability of the power supply.

 

[setbit]

Periodic reboot suggests insufficient peak current capability of the power supply.

Hi FvM, It is absolutely good idea, but I checked the power on the WH-LTE-7S1-E, and it is stable, no glitch at all.
I connected to an other, 5A power supply directly, but the problem remained.
Intrestingly, it seems, the module itself pull down it's RELOAD pin for 3 sec periodically.
My circuit do not connect to RELOAD pin at all, and the module has inner pull up.