Questions tagged [simcom]
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16
questions
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0answers
36 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 ...
1
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0answers
33 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 and the module has an onboard SIM7600A. I've been reading the documentation and although all the commands work as they are ...
1
vote
1answer
38 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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0answers
43 views
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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1answer
47 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&...
0
votes
1answer
155 views
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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0answers
33 views
SIMCOM SIM800C Delayed Power ON
In our product, we are using SIM800C for server communication. A few of our SIM800C are not getting ON immediately after power up. But after 15-20 seconds, the network status LED starts blinking and ...
0
votes
2answers
1k views
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 ...
1
vote
2answers
648 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 ...
0
votes
2answers
283 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 ...
1
vote
1answer
385 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" ...
5
votes
1answer
1k 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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2answers
339 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 ...
0
votes
0answers
958 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 < ...
0
votes
2answers
2k 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 ...
3
votes
1answer
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 ...
