Questions tagged [sim800]
The sim800 tag has no usage guidance.
23 questions
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Some characters lost in UART Transmission (PIC12F1822 -> SIM800L)
I am using the diagram recommended in the SIM800L datasheet to connect it to a PIC12F1822 MCU operating at 3.3V and 16MHz using its internal RC oscillator.
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- 289
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1
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103
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How to simulate a finger touch electrically to remove noise
I am working on a project with "SIM800L" GSM module, the problem is that there is a noise from the module in the calls and it disappears when I touch the module's body with my hand.
Kindly, ...
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53
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Sim7600 TLS data buffer size?
I use sim7600 module's TLS layer to connect the Azure IoT hub. I have problem with tls buffer size, which is 2kb(as datasheet says). It acts unexpectedly when i try to receive message more than 2kb in ...
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336
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Sim800L can't send SMS
I know it is somehow weird problem, but I don't know what to do.
I am using SIM800L GSM module with ESP8266 nodemsu v3 and they are connected via UART serial communication.
I am using this code to ...
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227
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Can't get DTMF tones from sim800L gsm module
I am using esp8266 and sim800L gsm module to recieve incoming call and get the DTMF tones from the caller and take an action according to the received number, i am searching for about 3 days and found ...
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110
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SIM800C not working as expected
I've created a custom board with a SIM800C. I'll show the schematic above:
My VIN is aproximately 4.8V. MY "4V" line is constant. I'm able to comunicate with the module, but sometime's ...
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2
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639
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SIM800L external supply issue
I have built an Arduino project that sends data from sensors to a specific website using the SIM800L GSM module. My problem is when I power whole circuit it from a computer or a charger, it works fine....
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163
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Why does the SIM800C stop sending data to the server after three days of continuous use?
I created a device that monitors air quality. The measured data is then sent to a web server using an ESP32 (programmed in C++ with Arduino framework) and SIM800C module, which stores them in an ...
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74
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SIM900A: Network depersonalization required
I have made experience with sim 800l, it works like a charm. Now I got a new SIM900A module, interferencing it with (RP over python), AT command returns ok, and other basic AT commands, so not the ...
- 21
3
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1
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520
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STM32F401 UART noise
I have device with an STM32F401 and a SIM800L. When the SIM800L sends data I have noise (usually 1 byte) received by the STM32 on UART2 connected to the SIM800. If I use FTDI instead of STM32 I never ...
- 131
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451
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Guide for power supply for ATMega328 and SIM800L project
I am creating a data logger that uses:
ATMega328p - microcontroller
SD card module to read and write data
SIM800l - modem to transmit data from SD card to API
OLED I2C display
DHT22 temperature ...
- 121
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237
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How to combine SIM800L and Ethernet shield in one program?
I'm trying to use a SIM800L and Ethernet shield in one program. Separately they work perfectly, but they do not work together.
When I put the following code in the ...
- 111
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2k
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Send data to MQTT broker using SIM800 and ESP32
I'm working on a project in which I need to send data to an MQTT broker installed on a Raspberry Pi.
I refer to the tinyGSM library and this tutorial along with this example.
The ESP32 remains in ...
1
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0
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206
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Gate of Logic level MOSFET connect to Esp32 gpio
I want to use IRLR024N logic MOSFET to switch on/off a Sim800L module. This module consume 2A for 500μs and then consume only 200mA. I supply this module with 4V. This MOSFET able to switch on this ...
- 77
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1
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289
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SIM800L power switching with transistor
I use a TIP32C transistor to switch the power line of a SIM800L module, but unfortunately this method isn't working. The module is powered on, but it only blinks once every second instead of every 3s. ...
- 77
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167
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Li-ion battery load sharing
I'm designing a backup battery for some portable sim800 project.
In this application note, page 5 it counts problems of connecting load to battery directly.
but for example in this schematic of ...
- 11
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2
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2k
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SIM800L V2 not responding to AT Commands from Putty over USB-To-TTL PL2303
My SIM800L V2 RoHS (the blue one) although it connects to the network and registers just fine, it's not responding to AT commands sent over the PL2303 (USB-STC-ISP) USB-To-TTL Adapter through which it'...
- 21
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1
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567
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SIM800C does not work (state LED does not toggle/set)
I am trying to use a SIM800C GSM/GPRS module for my project. On the datasheet it says:
The power supply range of SIM800C is from 3.4 V to 4.4 V. Recommended voltage is 4.0 V. The transmitting burst ...
- 211
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182
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SIM800c does not power up by pulling down PWR KEY
As far as I understand if I put power and gnd connections to SIM800c (chip), and then I pull down the PWR KEY for 1s it is supposed to turn on . The status should show voltage.
But in my case I have ...
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889
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SIM800L sends back the same AT command String that was sent to it from ESP32
My objective is to send the command AT to the SIM800L board and receive an OK. The problem is the data being received through the serial is exactly the same that was sent to the SIM800L module: the ...
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2
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166
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VBAT vs 4V on this circuit. What is the difference?
Schematic can be found here
I am trying to understand and replicate the schematic.
Why doesn't the author use DVDD4V4 for the ADC and he/she uses VBAT instead?
Can I just connect to ADC the DVDD4V4?
I ...
- 125
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2
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574
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CE marking of devices using pre-certified radio modules without antenna, just a 50 ohm RF port
I'm right now working on a project involving 2 radio modules, a SIM800F and a LoRa1276-C1-868.
The modules are already certified under the radio equipment directive. In the case of the LoRa module it ...
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1
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9k
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SIM800L AT+CSQ return 0,0 when SIM is inserted and 20~40 when I insert the sim
I have SIM800L module,
when I try AT+CSQ it returns 0,0
when I tried to remove the sim and try again it returns number, 0 (25,0)
and I cannot register to a network
so AT+CREG? returns 0,2
should ...
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