Microscan QX-830 - Appendix H Glossary

QX-830 Compact Industrial Scanner User’s Manual A-83
Appendices
Appendix H — Glossary of Terms
AGC — See Automatic Gain Control.
Analog — A smooth, continuous voltage or current signal or function whose magnitude
(value) is the information.
Automatic Gain Control (AGC) — Adjustment to signal strength that seeks to maintain a
constant level regardless of the distance between a scanner and symbol.
Baud Rate — The number of discrete signal events per second; bits per second.
Check Character — A Modulus 43 or Modulus 10 character that is added to encoded
symbol data for additional data integrity.
Connector — A plug or socket on a device or cable providing in/out connectivity for various
circuits and pins.
Concentrator — Intermediary device that relays data from scanners to a host and commands
from the host to the scanners or other devices.
Counter — Memory space allocated to keep track of scanner events.
Daisy Chain — Linkage of primary and secondary scanners allowing data to be sent to
the host.
Decode — A good read. The successful interpretation and output of the information
encoded in a symbol.
Default — Restores non-volatile or flash memory settings, initializes serial commands,
and resets all counters.
Delimited — A delimited command or field is bracketed by predefined characters.
Decode Rate — The number of good reads per second ahieved by a scanner.
Discrete I/O — Inputs and outputs characterized by discrete signal transitions from one
voltage level to another so that digital switching can occur.
End of Read Cycle — The time or condition at which the scanner stops expecting symbol
information to decode.
External Edge — Allows a read cycle to be initiated by a trigger signal from an object
detector when it detects the appearance of an object. The read cycle ends with a good
read, a timeout, or a new trigger.
External Level — Allows a read cycle to be initiated by a trigger signal from a photo
sensor. The read cycle ends when the object moves out of the detector’s range.
Firmware — Software hard-coded in non-volatile memory and closely tied to specific
pieces of hardware.
Fixed Symbol Length — Increases data integrity by ensuring that only one symbol length
will be accepted.
Full Duplex — A communication system in which signals can travel simultaneously
between devices.
Gain — Optimal signal strength.
Good Read — A decode. The successful scanning and decoding of the information
encoded in a symbol.