Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [sim]

A SIM card is a card in a GSM cell phone that tells the network about the phone, e.g. for authorization.

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Determine the operating voltage of a SIM card

I'm trying to get my SmartCard reader to communicate with my phone's SIM card. I have a level shifter to drive 1.8V and 3.0V SIM cards, but the Wikipedia article specifies that there are also 5.0V SIM card. I just want to be sure that my SIM card is…
Randomblue
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Ways of Switching between Two Sim Cards

I'm interested in building a circuit to switch between 2 sim cards, and found a design guide by GSM module manufacturer Telit. (New design guide link here, see pg. 16+) In particular, "Figure 6" of this guide shows the use of a p-channel MOSFET to…
PDug
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SIM card: Detected when the card is removed

I have an STM32 with a SIM card reader. For some reason the DETECT pin interrupt is triggered when the SIM card is removed, as opposed to when the SIM card is inserted. What could be going wrong here?
Randomblue
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Make a simple sim card reader circuit

I'm trying to implement a sim-card reader for my own. I followed step by step the guide on www.ladyada.net site but it does not work as it would be. My PC and softwares i used to read/write data from/to sim-card could't recognize my sim-card reader.…
sadclown2006
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M2M vs normal SIM cards

I recently bought some global 3G modules from Digi International and wanted to test one of them with the SIM card from my phone. I was surprised when I saw the module couldn't connect to the network. So I then used a prepaid SIM card from the same…
Andres
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Electrical reset to a SIM card

I have a SIM card reader connected to an ARM, and I'm trying to get the SIM to send an Answer To Reset (ATR) and to get the reader to capture it. As I understand, an ATR is sent after an "electrical reset" by the card to the reader. Now in my…
Randomblue
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SIM card for SIM908 module

I just got this SIM908 dev board, and I'm trying to get it working. However, it keeps telling me "SIM not inserted": AT+CPIN? +CME ERROR: SIM not inserted which of course causes other operations to fail: AT+COPS=? +COPS:…
Isvara
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SIM800 doesn't give GSM location

I have problem to get exact GSM location using SIM800L. I have followed instructions in the manual. But my module just gived me latitude = 0 and longitude = 0. This is what I do with my serial…
SkyFrotza
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How does a cellular network deal with a duplicate SIM?

I was pointed here from WorldBuilding. 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. If I were to call someone on cellphone A, what exactly would happen to…
zeph
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What kind of SIM are these?

I have a device (XT107) that requires a SIM card. It takes a SIM card that have copper plate (not sure what to call that) that supports all 8 circuits on the device. When speaking with people, some say it's a 2G SIM card, but I doubt that since…
Syska
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Save data on sim card using micro-controller

SIM cards come in various data capacities, from 8 KB to at least 256 KB. All allow a maximum of 250 contacts to be stored on the SIM, Is it possible to save data (other then contacts) in sim card, interfacing it with micro-controller then transfer…
Jon
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SIM card as IC component?

I read somewhere a few weeks back that a company is making SIM cards as IC chips for the "Internet of things". I can not find the article again or find anything about it on Google. Did I make this up?
MadHatter
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Is it possible to multiplex SIM cards using a CPLD?

I am building a hobby project using a GSM module and would like to be able to switch between multiple SIM cards, in case one stops working or I have poor reception on one provider (the project will be quite inaccessible once deployed). Would there…
user5077257
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Push-Push SIM card holder ESD protection required?

We are using this SIM card holder in one of our designs. The SIM card can be inserted into the slot and fixed/released by gently pushing it in. So the contacts are protected from touching. Would you still consider adding the common ESD protection…
Rev
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SIM card used as secure storage with AVR

I would like to use a regular SIM card to store an AES key to be used by an AVR micro-controller. I think that a SIM is secure enough (isn't it?). My problem is that I can find nothing about interfacing a SIM card with Arduino (for prototyping) as…
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