Questions tagged [simcom]

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SIM7080 UART Noise interfacing with PIC18F4550

I'm working on a project where I read data over Modbus line and send it in the cloud service through a SIM7080 CATM modem. I'm using PIC18F4550 as MCU. As that PIC18F has just one UART module, I'm ...
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Help with troubleshooting SIM 7600 with arduino for HTTP GET requests

I have got SIM7600 working with Arduino to update GPS coordinates obtained from UBLOX M8N to a custom URL using http get requests. My code works fine and I am able to track the GPS coordinates. ...
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SIMCOM 7080G Unsure about the RFGRFC INTERFACE

been reading through the SIMCOM 7080G HARDWARE manual and on 3.12 it has a RFGRFC interface circuit. what type of RF Tuner IC uses these ANT_CONTROL lines like this ? or is this just an RF switcher ...
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445 views

Assisted GPS (AGPS) on SIM7600 module does not work

I recently got a SIM7600G breakout board and wanted to use it with the CGPS functionality for A-GPS. It works with connecting with my SIM to the Internet and all, but when I try to use AT+CGPS=1,3 (UE-...
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UART IO not working, placed multimeter to measure voltage and IO began working instantly - why?

We are a bit stumped on this and wanted to see if anyone had any experience or perspective on this. Description of Event We are communicating via UART from a 3.3V processor to a Sim7000G (1.6-1.8v). ...
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SIM808 freezes after one SMS using STM32

I am trying to design a GPS car tracker with a SIM808 module using a STM32F103RET6 header board. I want to get the location link messaged to my phone by sending an SMS to the module. Right now, my ...
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78 views

Putty won't allow me to type. Can only type the letter 'A'

I connected a SIM7605CE module to the PC (Image shown below). I downloaded and installed all the necessary firmware for the device. I connected the device to a 5V DC power supply and connected it to ...
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Are there regional constraints with the SIMCom modules? (Eg. SIM7605CE/SIM7600CE)

I recently received a SIMCom Module (Model no. SIM7605CE), shown below. The item can be (purchased online as well). The device, much like the ones used with Arduinos (like the SIM800L), is supposed ...
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48 views

Why I've weak Bluetooth signal with Sim800C and how to strengthen it?

I've designed a circuit and used SIM800C module to work with its standard Bluetooth and GSM module. GSM works well, but its Bluetooth has weak signal, which I've to stick my phone to the board. In ...
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492 views

SIM7600A gives an error when executing commands, but works after executing it again

I am currently using a WaveShare cellular modem hat for my Raspberry Pi. The module has an onboard SIM7600A. I've been reading the documentation and although all the commands work as they are ...
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76 views

ESD clamping voltage in SIMCard interface too high

I planned to use SIM868 and what makes me confused all this time while choosing ESD protection is the voltage after clamping the transient voltage, it is still way too high especially when looking at ...
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Send data over server from microcontroller

How large chunk data of data is send over internet using GSM module or ESP from some kind of microcontroller. As they both have a limit of data sent by TCP so how is it done and what is used to ...
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1 answer
68 views

SIM7000E modem stops sending SEND OK reply

I am using a SIMCOM SIM7000E modem to send data using MQTT. Usually modem reply correctly to AT+CIPSEND command and sent ">" to enter the required data and then reply with "SEND OK&...
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SIM868 powers down after few seconds

I designed a circuit with SIM868 module, and i followed the recommendation from datasheet to unsure suffusion current. The main power supply is getting from VCC:12V source converted to 5V by an DC-DC ...
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stm32f107 uart frame and noise error

I made a device with a stm32f107 and sim800l gsm module . Module is in data mode(PPP) and I'm using LWIP library . My MCU clocks at 72MHz . My problem is that I get frame error and noise error when ...
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1k views

STM32F4 and SIM800L logic level

I am currently using an STM32F401RE that I have to interface with a SIM800L GSM module via UART. In a first "toy example" I used Arduino and found no problems, but passing to the STM MCU I am unable ...
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425 views

Mcu keeps reseting because of noise

I have a circuit in which there is a mcu lpc1768 and a gsm module sim800l. For power I use DC/DC converter and made a 4.2v using lm2576 for sim800l. Used that voltage, I made a 3.3v using ams1117 and ...
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1 vote
1 answer
500 views

SIM800C returns +HTTPACTION: 1,602,0 during HTTP GET

I have several boards with SIM800C GSM module. One of them works correctly when I issue HTTP GET request (returns HTTP 200). All other boards returns HTTP 602 all the time. 602 stands for "No memory" ...
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5 votes
1 answer
2k views

SIM808 registration denied for new SIMs

I have a SIMCom SIM808 2G GSM module on a custom PCB based upon the Adafruit FONA. I got a bunch of 2G SIM cards from Aeris.net. The problem is when I first put the SIM cards in my device, I get "...
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387 views

SIM808 always returns the same temperature

I have a SIMCom SIM808 module built up on my own breakout board. Whenever I query the temperature I get back the exact same temperature, 24.11 (deg C) despite the actual temperature in the room ...
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1k views

Enabling SD card access on SIM808

I am currently working with SIMCom's SIM808 2G+GPS modem. In my setup, an MCU communicates with the modem over UART to save some data in the SIM808's filesystem. As the modem's built-in memory is < ...
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2 answers
3k views

Can't reduce SIM808 Power Consumption

I bought a SIM808 module to use it with a PIC microcontroller. Everything works great but now I'm trying to reduce the module power consumption. The module I have is this one from DFRobot. When the ...
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3 votes
1 answer
2k views

SIMCOM vs UBLOX [closed]

I would like to know what are your thoughts on the following below. I am designing a GSM tracking device with a SIMCOM808 module and I am speaking to an antenna supplier that advises me to rather go ...
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