Picture 1
Today, there are virtually no Internet resources that would not need your phone number. Verification of the number is usually done by receiving an SMS with a code or a call, where the last digits of the number are an argument for confirmation. If you are engaged in a business, you have probably come across the fact that in order to perform certain banking operations, you must sign them using a code from SMS. Everything is fine when you are in your home region and getting a code is not difficult, the situation is much more complicated if you are in another region where roaming does not work, because your phone or SIM card is not supported by local mobile operators. One of the elegant solutions is this project (Figure 1). In the home region, you leave the M5Stack with a SIM card installed, get a white IPwith the operator, open the port and get access to the log of incoming SMS and calls online from anywhere in the world where there is Internet.
There are no modems, but you hold on!
There is no built-in modem out of the box in the M5Stack Basic device and there is nowhere to insert a SIM card, so you need to additionally purchase a GSM module (you can select it from the link ).
Please when choosing make sure you have no sins behind yoube especially selective ... If you look at the datasheet on the SIM800L , it says so:
4.1. Power Supply
The power supply range of SIM800L is from 3.4V to 4.4V. Recommended voltage is 4.0V. The transmitting burst will cause voltage drop and the power supply must be able to provide sufficient current up to 2A. For the VBAT input, a bypass capacitor (low ESR) such as a 100 μF is strongly recommended.
Do you know what I mean? The dropper. My Air, on which I write the code, does not give a current of up to 2 A. We open the braid of the USB-C cable, cut what wire? Red. We connect an external power supply to 5 Volts 3 Amperesfor surein place of the incision. Now the power of the Basic device will go from an external power source (and everything will be fine - I thought). But the modem did not think so. For him there was too much ~ 4.8 Volts and he screamed in every possible way with his only LED.
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int web_port = 80;
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String web_mainPage = "GSMout";
data – SPIFFS- Arduino IDE, ESP32 Sketch Data Upload ( ), () myHomeHotspot.wifi, myHomeHotspot — Wi-Fi-, – . Wi-Fi.
Wi-Fi-, , NTP, . , watchCat - . , - . .
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Video demonstration of work can be seen here.