Matrix user forums

Hello Stuart, I thought it best to open a new topic

http://www.matrixtsl.com/mmforums/viewt ... =50#p77029

Can you please help me with the component SIM800L, as I see you did work; probe with examples published in The Matrix and you posted in the forum but I can not make it work; I'm feeding the PIC and SIM800 with 3.3v, the TX pin SIM800 is connected to C7 and RX pin SIM800 is connected to C6; I am posting a simple example, just that the connection is achieved.

I appreciate if someone could help

Thanks
Enrique

Hello Enrique,

Have you done a 1 second flasher test to confirm your clock speed and config settings are ok.

http://www.matrixtsl.com/wiki/index.php ... ED_flasher

Also what current can your 3V3 supply handle? Note that the datasheet states a power supply of 3.4V - 4.4V. 3V3 may simply be too low.

I have used these modules before by powering everything using a single cell Lipo battery which gives a voltage between 3.7V and 4.2V. The Lipo cell should also be able to feed the high current spikes the GSM module requires which can be as high as 2A.

Hello Benj

I have a current of 3.3v, 700mA, maybe it could be the current, the connections are correct, I will do these recommending me.

I will make a test.

Thanks Benj

Enrique

Hi Enrique,

Sounds like it could be both the current and the voltage. The datasheet specifically states 3.4V as the absolute minimum.

Hi Benj

I found a source of 0-24V 3 Amps, I will do tests this source to 4 volt, 3 Amp

Thanks
Enrique

Hi Enrique,

That sounds good, fingers crossed that should solve the issues you're having. Let us know how you get on.

Hi Benj,

test the circuit this day, I'll let you know the result

Thank Benj
Enrique

Hi Benj

Thank you, Benj, I am very happy, (After many tests) the problem was the voltage and current probe is an example that receives and transmits messages and works perfectly.

I appreciate the help you gave me

Enrique

Brilliant, glad it's working correctly now. Very nice little modules but tricky to power them correctly.

Hi Benj,

Yes. . . knowing how to connect and feed components, it is the basis of properly functioning.

thanks a lot, Benj

Enrique

I used the simple flowcode from Enrique SIM800_HOLA.fcfx. But initialising the GSM module SIM800L gives the message "No reply"(255). The red LED on the GSM module stays flickering. Has someone an idea what is wrong? I used a SIM card from my mobile phone, which needs in the phone a code. Is that a safety of the phone or is that code part of the SIM?

Kind regards

Jan

Hello Jan,

the led of the sim800l module flashes continuously fast when no signal is detected, when the module detects signal and the communication is linked to the sim, the led flashes slowly between 2 to 3 seconds between a flashing and another.

You can exchange the sim of other companies and do not require codes (Mexico)

The power voltage is important, I use 4.2 volt

Regards

Dear Enrique

Initilising the SIM800L gives directly code 255 (no reply). What does it means? No good communication between the microchip and the SIM800L? Or can there be an other reason?

Kind regards

Jan

Hello Jan,

I do not know what failure 255 (NO REPLY); in my projects with the GSM module it generates code 0 (ok), from the first second that I connect to the GSM power supply, it generates OK, even when I'm still the signal is not linked to the GSM, the LED flashes quickly and then slowly and in both cases it keeps me OK, I think it is the connection between the GSM and the PIC. . .

Best Regards

Enrique