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The Central Processing Unit | |||
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The CPU is usually an 8-bit microprocessor with a 16-bit address bus.
This makes it possible for this type of processor cards to address up
to a maximum of 64 KB. |
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The CO-Processor | |||
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The more advanced cards are provided with a co-processor, which perform
the exponential and modular operations on integers when handling
encryption procedures, for example with digital signatures. |
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The I/O Port | |||
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The I/O port is used to transfer the data in a serial fashion, bit by bit. The
default speed is 9600 bits per second; some cards support higher speeds. |
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The Memory | |||
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Memory is very important for a smart card as the more memory it has, it
will allow more data and more sophisticated programs to be stored. There
are a few different types of memory that are being used in the smart card
and depending on the applications, the appropriate memory is used. |
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Random Access Memory (RAM) | |||
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RAM is the fastest form of memory that the chip can access. However, it
is the most volatile and will lose all information when there the power
is cut off. Data stored here could be written on and change easily. Thus,
it is often used as a buffer or temporary storage. |
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Read Only Memory (ROM) | |||
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ROM is a non-volatile memory as data is stored in there permanently. Data
stored here could not be written to or readable by the users. Thus, it is
usually use to stored the basic operating system programs when the smart
card is being operated or used. |
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Erasable Programmable Read Only Memory (EPROM) | |||
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EPROM is a non-volatile memory as data could only be written once and could
only be erased using ultraviolet light. It protects data from potential
hackers as the data stored there can not be altered nor erased easily. |
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Electrically Erasable Programmable Read Only Memory (EEPROM) | |||
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EEPROM is a non-volatile memory technology where data could only be
electrically erased and rewritten by a reader/writer device. It is usually
used for stored value cards and information management applications. |
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