A problem with the SIM900 module I want to connect to an STM32F4

[deta]

Hello everyone, I have a weird problem. At my internship, I was given a SIM900 and SIM7600 module and told to make projects based on them, yet I cannot find these modules anywhere on the internet. The project I wish to do with the SIM900 is thus: Send an SMS to my phone. Here is the SIM900 module I was given:

Here is the SIM7600 module, which is approx. the same:

I have decided that the best course of action from this point onwards would be to try to use the pins of the chip itself to suit my needs. That is fine. What strikes me as odd is that I cannot, for the life of me, find these things anywhere. Are there any alternate sources I can try? I wrote the numbers on the cards into Google, I did Google reverse search, I tried to read the pins and figure out any distinct features but the SD card is the only one I can think of--which led me nowhere new. 

Is my research simply insufficient? Thank you for your time.

[Andrew Neil · Accepted solution]

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@deta wrote:

I have a weird problem. At my internship, I was given a SIM900 and SIM7600 module and told to make projects based on them, yet I cannot find these modules anywhere on the internet.

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The SIM900 and SIM7600 modules themselves are widely used and well documented; eg,

https://en.simcom.com/product/SIM7600X.html

https://www.allaboutcircuits.com/electronic-components/datasheet/SIM900--Simcom/

although it appears that SIM900 is no longer supported by SIMCOM - it gives no hits on their website.

Are you really asking about those boards on which your modules are mounted?

If you've been given them, then it's really the duty of the person who gave them to you to provide the necessary documentation - unless this is intended as an exercise in reverse-engineering?

None of this has anything to do with ST or STM32.

EDIT:

There are plenty of well-documented and supported cellular boards available - so, if you can't find documentation for these boards, there seems little point in messing about with them.

If you do want something from ST, see the B-L462E-CELL1 and X-CUBE-CELLULAR:

https://www.st.com/en/evaluation-tools/b-l462e-cell1.html 

https://www.st.com/en/embedded-software/x-cube-cellular.html 

[deta]

Yes, I am actually asking about the boards, sorry about that! I have decided to just use the module itself and not pay mind to the board. They kinda threw these at me and told me this was all they had in the way of cellular modules, so maybe it is reverse engineering? Though I doubt they have easy access to its documentation. I have asked in a lot of other forums but got no answers so I thought I'd try here as a last resort, sorry about that as well.

[Andrew Neil]

This is a poor way to treat an Intern.

You should be pushing this back to your supervisors!

There are plenty of low-cost boards in Arduino Shield formats - that would be the obvious way to go.

Note that the SIM900 is 2G, and 2G networks are being shut down across the world - some places no longer have 2G service ...

[deta]

Thank you for your concern and your knowledge, I'll try to make it work. In the worst case, I'll tell them I wasn't able to figure out what to do with these boards.

[Andrew Neil]

It's better to feed back earlier rather than later.

Tell them now that there is no documentation; ask them if they really want you to waste spend your time faffing about with them.