ABA
American Bankers Association. This association set a standard used in Magnetic Stripe credit cards. The standard format uses specific start and stop characters and typically uses track two of a four-track card. Example: ABA Track two format.

AC
Alternating Current, used as a primary power source for the access system.

AMP
A measure of current for AC and DC voltages. A milliamp (mA) = 1/1000 of an Amp.

Anti-passback
A feature that prevents a user from giving their code to someone else to use. A user code must be used to enter then used to exit before it can be reused to enter again. This feature requires one port for entry and a second port for exit.

ASP
Advantage Series Proximity. A technology employed in Corby's proximity cards. This technology does not require an internal battery to power the card thus drastically improving the life span of the card.

AT
Designation specifying an 80286 based personal computer.

AWG
American Wire Gauge, denotes the size of wire conductors used in a system.

Batch
A group of users with the same door permission and restrictions.

BCD
Binary Coded Decimal. A parallel method of encoding digital data.

Baud Rate
Speed at which serial data is being transmitted. 14,400, 9600, 2400 etc.

Bonding
As it applies to grounding. The joining of metal parts in a building (beams, plumbing, grounds, etc.) to form an electrically path to earth ground for the purpose of safety.

Card
A plastic Card containing user ID information. Cards come in four different technologies Bar Code, Magnetic Stripe, Proximity and Wiegand. This Card is inserted into, swiped through, or presented to a reader.

Code
A sequence of digits which are sensed by the System when the user enters a Card or presses numbered Keypad buttons.

Code 39
A Bar-Code symbology also known as "code 3 of 9".

COMMAND
An instruction. Tell the system to perform a function.

CPU
Central Processing Unit. Usually the main microprocessor in the system.

CSA
Canadian Standards Association which sets standards for conductor style and temperature ratings.

CTS
Clear to Send. An RS-232 input on the system that tells a transmitting device attached to it that its OK to transmit its data.

Data Chip
A stainless steel canister, the size of two stacked dimes, containing an integrated circuit that sends a 64 bit number when touched to a reader designed for the purpose.

DC
Direct Current. A type of voltage usually specified as having a positive and negative source.

Default
Preset values in the software which the System will use if the user does not change them.

Disabled
Turned off. Not active.

Door Ajar
A condition that occurs when a door is left open after a valid user has passed through.

DPM
Door Port Module. Steel locking cabinet which contains the CPU, PCB, RAM, EPROM, standby battery, and connection terminals.

Earth Ground
A direct electrical path to earth. Usually a cold water pipe, the steel beams of a building, or a steel rod driven at least six feet into the earth and bonded to the Electrical System as defined by the National Electrical Code.

EMULATOR
A software program that configures a personal computer (PC) to act as a Video Display Terminal (VDT).

Enabled
Turned on. Active.

Enter
To type information on the System in response to a prompt. To complete the entering of a code or command by pressing the #.

EPROM
A non-volatile memory chip used in the system which contains all instructions and operates the system. EPROMs retain all information without the need for backup power.

EEPROM
Electrically Erasable Programmable Read Only Memory. A memory chip used in the System that contains special information. EEPROMs retain all information without the need for backup power.

ESN
Electronic Serial Number. A 64 bit number, permanently programmed into a non-volatile memory device. Used to identify a particular unit, date of manufacture and other parameters.

Events
An action, condition or something that happens on the access system and becomes part of the information stored in the event data base. Event conditions can be used to trigger auxiliary outputs.

Fail-Safe
If and when power to the door fails, the door will be made permanently-open and allow entrance or exit without the need for access control codes or Cards.

Fail-Secure
If and when power to the door fails, the door will be made permanently closed and will not allow entry or exit.

FAIL-SOFT
If and when power to the portal (door) fails, the portal will be made permanently-closed and will not allow entrance and/or exit.

Forced Entry
A condition that exists when a door is forced open prior to a valid user entering the door.

Form A Relay
A type of relay that has a single pole, single throw, normally open contact.

Form C Relay
A type of relay which has contacts including a common, a normally open (NO) leg and a normally closed (NC) leg.

Ground
A direct electrical path to earth ground. Usually a cold water pipe, the steel beams of a building, or a steel rod which is driven into the earth and bonded to the Electrical System as defined by the National Electrical Code.

Initializing
The automatic process of configuring the system at power-up. Default values are set and memory is tested.

LED
Light Emitting Diode. A semiconductor device that emits light.

Magnetic Stripe
Card technology that uses a Magnetic Stripe to hold its data. System 2 uses a track 2 ABA format.

Master
A system unit, programmed to be part of a network of systems and in control of "slaves" on the network.

MCU
Master Control Unit. Steel locking cabinet which contains the CPU, PCB, RAM, EPROM, standby battery, and connection terminals.

Modem
A device that connects to a telephone line for the purpose of sending and receiving digital data. Modems are rated by their speed or "Baud Rate." Example 9600 Baud.

MTBF
Mean Time Between Failures.

National Electrical Code
A document published by the National Fire Protection Association. Its purpose is the practical safeguarding of persons and property from hazards arising from the use of electricity.

Networking
The ability of system's to be linked together. A multi-drop, twisted pair of wire is connected to each system unit in the network in a daisy-chain fashion.

NULL MODEM
A passive, connector type of device which reverse the pin positions of the RS- 232 transmit data and receive data lines.

PCB
Printed Circuit Board. This board contains the electrical components of the system.

PIN
Personal Identification Number. A number which is unique to each user of the system, and is entered at a Keypad in order to gain access.

Port
A designation given to all the input and output connections required to operate a door. It may contain an input for RTE, Door Ajar, Keypad, Card Reader etc. and a relay output for controlling the door.

Power Supply
A source of power for the access system, door locks and auxiliary devices. Usually consists of a plug in transformer, circuit board and standby battery. Power supplies are rated by their voltage and current capacity.

Prompt
A cue. When programming, the System will "ask" you to enter various information. This "asking" is called a prompt.

Proximity
A type of card technology that sends wireless digital data from a card to a reader through means of an electrostatic coupling.

RAM
Random Access Memory. Semiconductor memory that can be both written to and read from. Specified by size (128K x 8).

RS-232
Data transmission standard using +/- 12 volt transitions to transmit digital data.

RS-485
Data transmission standard using differential voltage levels to send and receive data on a shielded, twisted pair of wire in a multi-drop configuration up to four thousand feet long. Highly immune to electrical noise.

RTE
Request to Exit. A circuit controlled by a push button installed within a secured area which, when pressed, allows a user to exit the area. RTE's should always be redundant, that is, a second method should be used to allow an exit.

RTS
Request to Send. An RS-232 output from the system. It tells a device attached to it that its OK to send data. Generally connected to the CTS of the sending device.

RXD
Receive Data. An RS-232 input that receives data from a transmitting device. This Input must be connected to the TXD output of the transmitting device.

Seed Number
A number used to generate an exact duplicate list of users when batch programming keypad codes.

Serial Number
A unique combination of digits and/or letters. All system software (firmware) and hardware is serialized.

Short Haul Modem
A type of modem that does not require a dial up phone line. Four wires are required between a pair of modems to send and receive digital data over distances of a few miles.

Slave
A system unit that is programmed to be part of a network of systems and under control of a master system.

SPDT
Single Pole Double Throw. Also a "C" form switch contact having a Normally Open (NO), Common and Normally Closed (NC) arrangement.

SPST
Single Pole Single Throw. A switch or relay contact having Commonand Normally Open (NO) or Normally Closed (NC) arrangement. Can also be referred to as a form "A" (NO) or form "B" (NC) contact.

Time Cancel
A feature that cancels any remaining door open time as soon as the door is closed.

TXD
Transmit Data. An RS-232 output that sends data to a receiving device. This output must be connected to the RXD input of the receiving device.

UL
Underwriters Laboratories. An organization that certifies the safety and functionality of electrical devices.

VDT
Video Display Terminal. Also known as a CRT ( Cathode Ray Tube) usually includes a keyboard assembly. Used to send and receive data to and from a computer device. Not a PC, although a PC can emulate a VDT with the proper software.

Watchdog
A circuit in the System that prevents microprocessor latch up. The watchdog circuit minimizes the likelihood that voltage transients will "crash" the system.

Wiegand Technology
Card technology that uses special patented wires imbedded inside the Card to encode its data.

X-10
The name of a product and protocol that sends digital information over existing AC wiring.

XT
Designation specifying an 8086 or 8088 based personal computer.