Mitsubishi Electric Apricot LS Pro, Техническое описание оборудования

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Chapter 1
Chapter 2
Chapter 6
Contents
Chapter 3
Chapter 5
System Board
Chapter 3
LS PRO HARDWARE TECHNICAL REFERENCE 3/19
The system microprocessor may determine if a password is currently installed with a
Test Password Installed command. This allows a controlling program to decide
whether or not to overwrite an existing password.
The system microprocessor may set a password in the 8042 at any time with a Load
Security command. Any existing password is lost, and the new password becomes the
active password. The password must be installed in scan code format.
The system microprocessor places the system in secure mode with the Enable Security
command. In secure mode the 8042 does not pass any information to the system
microprocessor. The 8042 intercepts the keyboard data stream and continuously
compares it with the installed password pattern. No keyboard or auxiliary device data
is passed to the system microprocessor until a match is found. When a match occurs
the 8042 is restored to its previous state and data is passed to the system microprocessor.
There is no limit to the number of times the password may be changed. No command
is available to verify the installed password. The 8042 accepts no commands when
keyboard security is active.
3.10 LOC TECHNOLOGY
The system board is fitted with a LOC Technology security subsystem. This subsystem
allows Apricot LOC Technology software to control access to data and facilities.
When Apricot LOC Technology is not in use the security hardware is passive and has
no effect on the system.
3.11 ETHERNET PORT
General
The Ethernet port on the system board is based around an 82596 Local Area Network
Coprocessor, an 82C503 Dual Serial Transceiver and an AMD7997. This provides a
port which complies fully with the IEEE 802.3, 10BASE5, 10BASE2 and 10BASET
specifications.
The coprocessor and dual serial transceiver make up an Ethernet controller for thick
cabling, and with an additional analog filter module a TPE controller. The 7997
interfaces between the thick and thin Ethernet cabling standards.
An expansion ROM socket may be fitted to the system board. This socket is intended
to allow for alternative remote boot ROMs. The system BIOS includes RPL remote
boot code.
The Ethernet standard defines a requirement for every device to have a unique address.
This is implemented in a PROM on the system board.