they are the bridge of various devices which described in 2-3. What devices
would connect with the IO and what the devices can be used that would be
explained as following in brief:
USB Host: This is USB 1.1 version on the SBC, connecting two kinds
of devices: USB camera and USB flash disk.
PS/2: The PS/2 connects with keypad module for entering the password
by the users.
Ethernet: For internet connection, and could be connected with home
network. The spec. is 10Mb.
RS232: The RS232 was applied to connect the RFID module whose
demand program would control the RFID module via RS232.
GPIO: The GPIO of the PCM-7130 can be programmed with interrupt
mode. In this thesis, it was applied with the communication between the
different processes.
DI/DO: The pure digital input and digital out was used for debugging
and simulating the door open status.
Audio: For alarm system used.
PCMCIA slot: Connected the wireless card.
2-3 Additional Peripherals
Except the primary hardware PCM-7130, the RFID module, keypad, USB
camera and USB flash disk and PCMCIA wireless card are peripherals in the system.
They were described separately in the following chapters.
2-3-1 RFID Module
The RFID full name is Radio frequency identification which is a
generic term for technologies that use radio waves, to automatically identify
people or objects. There are several methods of identification, but the most
common is to store a serial number (ex. UID) that identifies a person or
object, and perhaps other information, on a microchip that is attached to an
antenna. The antenna enables the chip to transmit the identification
information to a reader. The reader converts the radio waves reflected back
from the RFID tag, into digital information that can then be passed on to
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