Upgrading HTTP from HL to RC series

We have a firmware implementing AT+KHTTPPOST and AT+ KHTTPHEADER to send requests to our server from the HL and we are now refactoring the firmware to start working with the RC series. The RC series have removed those two commands and now I am not sure how we should create an HTTP request as the AT commands manual is not very clear on that.

The RC series still implements KHTTPGET but we need to send POST requests and set custom headers. From what I understand +KHTTPCNX should return CONNECT (as it starts the HTTP connection) so that we could simply send our custom HTTP message from the MCU to the module but from reading the manual, KHTTPCNX just returns OK so it doesn’t enter data mode.

How should we send an HTTP POST message with custom headers from the RC series? (without having to use a raw TCP socket).

Hi @guillermo,

I have just tested +KHTTPPOST and +KHTTPHEADER test command (AT+KHTTPPOST=? and AT+KHTTPHEADER=?) on RC7620 and observed the response with latest Firmware Release 6.2, published on https://source.sierrawireless.com/resources/airprime/software/rc76xx/rc76xx-firmware-release-6,-d-,2/#sthash.dlff0zYp.dpbs.

However, +KHTTPPOST and +KHTTPHEADER commands are not mentioned in latest AirPrime - RC76xx - AT Command Reference Guide here https://source.sierrawireless.com/resources/airprime/software/airprime---rc76xx---at-command-reference-guide/#sthash.HuDIYPiN.dpbs.

So, I think these command are not developed completely at this moment. Maybe, they will be released soon in next FW released.

If you are looking forward more detail information, you can contact to your distributor.


Hi @jerdung

Thank you for your help. We would like to avoid having to implement an HTTP client in our firmware.

Is it possible that you can test, with your RC series and the 6.2 firmware, a simple POST request like this:



accept: application/json



You should receive a HTTP/1.1 200 OK response.

Hi @guillermo,

Please refer to below for your request, I receive a HTTP/1.1 200 OK response.
Log is attached below:
sample.txt (987 Bytes)
However, I strongly recommend you should not use +KHTTPPOST and +KHTTPHEADER command until they are mentioned in document. These commands are not developed completely at this moment, so you can face the issues with current latest FW.


Amaizing @jerdung , even +KCNX_IND is working despite not being in the documentation either.

Is it possible to know if the intention of Sierra Wireless is to remove once and for all KHTTPPOST and KHTTPHEADER from the firmware or if instead the intention of the FW developers is to bring them back to the oficial set of commands? Those commands may be implemente but not actually in the documentation in order to provide backwards compatibility to old designs but the’ll be eventually removed. I am not sure if you are connected with the devs and can query them.

If the intention is to remove them in the future we will absolutely implement an HTTP client in our MCU, if instead the plan is to reincorporate them we’ll may evaluate the risk of using them in the mean time. We’re waiting to receive the samples and test them out.

Hi @guillermo,

So far I know, the +KHTTPPOST and +KHTTPHEADER commands are adding and developing in early 2021.

In the further future, I don’t know whether these commands will be removed. However, sure that I will notify to you once I got any update from these commands :slight_smile:

Please help to tick “Solution” if your question is answered.