Accu-Sort AXIOM 400 Product Manual Download

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AXIOM™ 400 Product Manual

Glossary

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A3-AXIOM400-Glossary_R10.doc

Accu-Sort Systems, inc.

The device also has a retransmit timer. This timer is activated each time
the device transmits data to the host. If the timer runs for two seconds
(this is also changeable) and the device does not receive an ACK or NAK
from the host, a timeout occurs and the device retransmits its data. Each
time the device retransmits because of a timeout, it treats the timeout the
same as receiving a NAK from the host computer. If the device does not
receive an ACK before the end of the fourth timeout, it will delete the data
in its transmit buffer and display “MAX REXMITS”. The device deletes data
in its transmit buffer and displays the error message when any
combination of four timeouts and NAKs from the host occurs.

When the device receives a message from the host, it calculates the BCC
for the message and compares the calculated BCC to the received BCC. If
the two values match, the device transmits an ACK, ending the
communication. If the values do not match, the device transmits a NAK to
the host and waits for the host to retransmit the message. The host, like
the device, should retransmit a maximum of three times.

The sequence number starts at zero (30H) and is incremented each time a
device transmits a new message. When the sequence number reaches nine
(39H), it wraps around to one (31H). If the sequence number skips a
number, the receiving device knows that a message was lost. If the same
sequence number is received on two sequential messages, the second
message is responded to with an ACK or NAK (as appropriate) and ignored.

shielding

Protective covering that eliminates electromagnetic and radio frequency
interference.

side read

The scanner is mounted to read the side of a box as it passes by the head.

signal

An impulse or fluctuating electrical quantity (i.e.: a voltage or current) the
variations of which represent changes in information.

skew

Rotation about the Y-axis. Rotational deviation from correct horizontal
and vertical orientation; may apply to single character, line or entire
encoded item.

slider bar

A graphical user interface that enables the user to select an
ascending/descending value for a definable parameter by clicking on the
slider bar and then sliding (via the mouse) until the desired value is shown.

software trigger

A serial message from an external device that controls the trigger cycle.

space

The lighter elements of a bar code symbol formed by the background
between bars.

specular reflections

A condition when the laser light is reflected back from the code’s surface
at an angle equal, or nearly equal, to the angle of incidence of the laser
light. This condition makes it difficult for the scan head to detect the
differences in light variation caused by the code’s bars and spaces.

spot

The undesirable presence of an area of low reflectance in a space. start
and stop characters

start bit

In asynchronous transmission, the first bit or element in each character,
normally a space, that prepares the receiving equipment for the reception
and registration of the character.

start and end of trigger photoeyes

The trigger cycle begins when the start of trigger photoeye is blocked and
continues until the end of trigger photoeye is unblocked. Relay decisions
and data communication take place after the end of triggeer photoeye is
unbroken.

stop bit

The last bit in an asynchronous transmission, used to indicate the end of a
character, normally a mark condition, which serves to return the line to its
idle or rest state.

STX (Start of Text)

A transmission control character that precedes a text and is used to
terminate a heading. (^B)

symbol

A combination of characters including start/stop and checksum characters,
as required, that form a complete scannable bar code.

symbologies

Codabar
Self-checking, numeric bar code encoding numbers and several characters
(e.g.: $, -, +, ?) with a slightly higher density than Code 39. Includes two
bar/space sizes.

Code 39
A bar code with a full alphanumeric character set, a unique start and stop
character, and three other characters. The name is derived from its code
structure, which is three wide elements out of a total of nine elements.
The nine elements consist of five bars and four spaces.

Code 93
Similar to Code 39 but requires two check characters. Code 93 was
designed to provide a higher density symbology with higher security than
Code 39. Although code 93 is a higher density, it is not self-checking and
therefore requires two checksums.

Code 128
A bar code symbology capable of encoding the full ASCII 128 character
set. It encodes these characters using fewer code elements per character
resulting in a more compact code. It features a unique start and stop
character for bidirectional and variable length decoding, both bar and
space character parity for character integrity, a check character for symbol
integrity, a function character for symbol linking, and spare function
characters for unique application definition and/or future expansion.

EAN
European Article Numbering System used in retail industry (a superset of
UPC) used on product packaging to uniquely identify a product and
manufacturer.

Interleaved 2 of 5 (I 2of5)
A bar code with a numeric character set with different start and stop
characters. The name is derived from the method used to encode two
characters. In the symbol, two characters are paired together using bars to
represent the first character and the spaces to represent the second. This
interleaved structure allows information to be encoded in both the bars
and the spaces. A start character, bar and space arrangement, at one end,
and a different stop character bar and space arrangement at the other
end, provide for bidirectional decoding of this symbol.

UPC
Acronym for Universal Product Code. The standard bar code type for retail
packaging in the United States and Canada.