Thales' cellular IoT products business is now part of Telit Cinterion, find out more.

You are here

at^sjmsec command on ELS61-E throwing error "wrong command format" | Telit Cinterion IoT Developer Community

June 14, 2021 - 3:36pm, 5846 views

Hi,

I'm testing communication to AWS IoT by adding server certificate and client certificate and private key.

As this is is a new PCBA HW with new chip (ELS61-E), I don't have access to modem chip via any demo board, everything has to be done via a MCU in between, which in turn communicate to the modem via UART.

I have been following instruction here: https://iot-developer.thalesgroup.com/showcase/concept-board-connection-...

I managed to transfer "AddHttpsCertificateUntrusted.bin" file over to the modem using AT^SJDL, and I know the content is correct because 1) the CRC returned from SJDL is correct and 2) I have readback the file content using AT^SFSA.

Now, when I try to install server certificate using the following command:

AT^SJMSEC="file",”AddHttpsCertificateUntrusted.bin”

I always got the following response:

appl> URC: at^SJMSEC="file",AddHttpsCertificateUntrusted.bin
URC: ^SJMSEC: 1,"wrong command format"
URC: +CME ERROR: invalid index

It looks like the server certificate is invalid, however, I don't have further information to see why. The server certificate is downloaded from https://www.amazontrust.com/repository/AmazonRootCA1.pem, and I upload the bin file here: https://www.mediafire.com/file/rno1mskdgs6nvcs/AddHttpsCertificateUntrus...

Any pointer to where the error might be is appreciated. Thanks!

Information

sending to modem : ATI1
received response: Cinterion
received response: ELS61-E R2
received response: REVISION 02.000
received response: A-REVISION 01.000.02
 
James