Sim card as external memory

[T.Suresh Pandi]

Hi,

    I am beginners to embedded system, i use P89V51RD2 kit for my testing, i have some doubt, please clarify
    1. What protocol used in SIM card.
    2. Can we use the sim card as external memory to the microcontroller.
    3. How to interface the sim card with 8051 microcontroller, please post circuit, and C code for that.
                Thank you,

 

[umar farrok]

SIM cards use a protocol based on an Open Systems Interconnection Reference Model.

Tranmission Protocols

• Information between the SIM and the device is sent via Protocol Data Units (TPDUs), for which there are two common protocols: T=0 and T=1. These protocols differ in the information structure by which the device and SIM card communicate.

• T=0

  The T=0 protocol is a byte-oriented protocol, meaning as little as one byte of information can be transferred in a given transmission. It uses a data structure that is sent from the device to the SIM and back, a process in which it establishes a command and response structure.

T=1

• T=1 is a protocol that enables blocks of data to be transferred between the SIM card and the device. These blocks are categorized as the supervisory block, information block and receive-ready block. A supervisory block controls data transfer, an information block enables the exchange of data between the SIM card and device application, and a receive-ready block acknowledges (or denies) a received block of information.

  yes we can use the sim memory as external memory , in addition to that only certain range of baud rate level it will work if you are assigning with micrcontroller 9600 baud rate is must .

[T.Suresh Pandi]

Thank you for reply Mr.Umar,

   How to write and retrive the value in particular address in sim card using microcontroller, i know only UART, I2C protocols, we can’t use UART for that, But i think we can use I2C, is this right ?.

[Author]

Posts