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5 votes

Why do some GPS devices require a GSM SIM-card?

Because the first is a GPS tracker that you can call and it replies via IVR or SMS or has a data connection so you can see it online or periodic emails. Maybe automatic geo fencing warnings. The ...
Passerby's user avatar
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5 votes
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How does a cellular network deal with a duplicate SIM?

Say I had a cellphone, let's call it cellphone A, and made a perfect copy of it - SIM card and all - and let's call this one cellphone B. Normally, your SIM card would be impossible to clone (it ...
Marcus Müller's user avatar
5 votes
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Is it possible to transfer provider from one SIM card to another?

If that "another" SIM card is not a blank one then most likely no, you can't. Even if you can, the new SIM will likely fail on network authentication due to the unknown or mismatched ...
Rohat Kılıç's user avatar
4 votes
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sim card power consumption

That depends on the mode and class the SIM is operated at. The electrical characteristics are defined in the ETSI TS 102 221. You'll find a copy online. Class-A (4.5V to 5.5V) you have: 200µA ...
Nils Pipenbrinck's user avatar
4 votes

SIM Cards are using a Microprocessor or Microcontroller?

It definitely is a microcontroller since it integrates a microprocessor, RAM memory, persistant memory, timers, I/O (7816 and optionally SPI, SWP, USB), security features and - often - a ...
PaulH's user avatar
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4 votes

SIM Cards are using a Microprocessor or Microcontroller?

A SIM Card is closer to a microcontroller than a microprocessor as it has all the required logic blocks including memory etc. It differs from a microcontroller because it is a dedicated application ...
le_top's user avatar
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Smart Card (SIM) clocking requirements

First, everything is specified in ISO7816-3. You should really read it (I won't provide any links because the standard is not free, but you can still easily find it on the web). Now, regarding your ...
dim's user avatar
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SIM800 PWRKEY - Automatic start

To automate the startup of sim800/sim900 module just keep the pwrkey shorted to ground always. As the supply will be provided modem will be on.
Pi M's user avatar
  • 56
4 votes

SIM800L restart automatically

You can't really read the voltage during the current spikes, the multimeter is not quick enough. GSM modules induce a large current spike during transmission and even larger during network ...
Jorge Gonçalves's user avatar
3 votes
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M2M vs normal SIM cards

There is no physical/electrical difference between the SIM cards. It is the economics of the network provider. When a device connects to a cellular network it provides its IMEI (serial number of the ...
filo's user avatar
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3 votes

One SIM card shared between two devices - IC?

It's not possible to share one SIM between two devices. Well, not easily, anyway. The SIM contains a microcontroller and there is quite a complex communication protocol between it and the device it's ...
Finbarr's user avatar
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3 votes
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PWM signal to SIM800 MIC noise reduction

The SIM800 has a microphone input. The signal you are getting from the microcontroller will be at too high a level for that input. The SIM800 expects an electret microphone, so maybe 100mV signal ...
JRE's user avatar
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Molex 5039600695: What is the SIM card stopper referring to?

The phrase "card stopper" is being used in two different ways here. In the top drawing, it's referring to a leaf spring that only gets lifted up out of the way if the beveled corner of the SIM card ...
Dave Tweed's user avatar
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GSM Data Post Over the GPRS Using GSM Modem

There isn't much information in your question, but I'll explain one common way you can solve this type of problem. In short: You need to get more troubleshooting data, and then use your critical ...
SamGibson's user avatar
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2 votes

SIM Cards are using a Microprocessor or Microcontroller?

SIM cards are UICCs, which integrate a CPU, memory, and I/O on a single device. The relevant reference is ETSI TR 102 216. ETSI - Smart Cards
Ignacio Vazquez-Abrams's user avatar
2 votes

SIM800 PWRKEY - Automatic start

I've just been reading through the SIM5360 datasheet and it points out that you can just connect PWRKEY to GND to ensure automatic startup of the module (SIM5360_Hardware_Design_V1.06.pdf, page 28), ...
Arya Voronova's user avatar
2 votes

I only hear quzz when making a phone call using SIM800L module

The microphone input on the SIM800 is ment to interface an electret microphone. The input sees a difference between the voltages on MICP and MICN as its signal. But the way it is connected now (R17 ...
peter's user avatar
  • 484
2 votes

SIM800 PWRKEY - Automatic start

You can connect the the PWRKEY to ground through a resistor and then command the module with an MCU GPIO port. Make sure to keep the GPIO LOW all the time, specially during startup so that the module ...
Mario's user avatar
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SIM7100 GSM Modem Unreliable Connection

I have found the problem, and may now give the answer to my own question. The optocoupler is broken, hence I removed it and Voila!
onrep's user avatar
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Save data on sim card using micro-controller

Absolutely. Except I am not sure if you are referring to smart cards or mobile specific SIM cards. Smart Cards are easy. They are like any other memory device. If you need to access a SIM card ...
Misunderstood's user avatar
2 votes

SIM to RJ: emulating SIM card as a RJ connector

You said in a comment: can you find any solution or a way? So now that you have removed the requirement in the original question, for connecting to that POTS phone via the RJ-11 connection - yes, ...
SamGibson's user avatar
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2 votes
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What could be done with a deactivated SIM card?

The SIM card contains the IMSI (International Mobile Subscriber Identity) number and the associated private key. The IMEI (International Mobile Equipment Identity) is part of the phone. Basically, ...
Simon Richter's user avatar
2 votes

SIM800 doesn't give GSM location

AT+CIPGSMLOC is using google servers to identify nearest GSM tower. That was discontinued few months ago. You can use triangulation using SIMCOM servers by upgrading to latest firmware ...
David's user avatar
  • 21
2 votes

Sim Card extender Circuit

You will be very unlikely to find a generic solution for remoting a SIM card. The reason is that whatever device is hosting the SIM card is going to have its own set of specifications and operational ...
Michael Karas's user avatar
2 votes

SIM800L GND pins

The four GND pins need special mention as only those pins carry the battery return currents and the other pins don't. It does not mean that other ground pins can be left unconnected. It just means ...
Justme's user avatar
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2 votes
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What is an epad in SIM MFF2 layout

It stands for exposed pad. They're intended for PCB heatsinking; you solder it to a large copper plane to pull heat away. They're often, but not always, internally connected to ground--look at the ...
Hearth's user avatar
  • 33k
2 votes

Why does the Atmega328 USART get trapped in a loop?

You cannot have the same UART wired to both the PC via USB serial and also the mobile modem, without causing such mixups. You need a second UART, either hardware or software as typical Arduino ...
Chris Stratton's user avatar
2 votes

Is it possible to transfer provider from one SIM card to another?

The subscriber identity module includes secrets known only to the provider, the only way is to get a replacement SIM from the cellular service provider and then have them change the account to use the ...
Jasen  Слава Україні's user avatar
1 vote

SIM800L restart automatically

the solution is simple. The module is poorly designed to run from other sources than the battery. There are 2A spikes at the VCC level. Changing the C3 capacitor will most likely fix module from ...
Jakub Miřejovský's user avatar

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