Microscan HS-2D Manuel d'utilisateur télécharger pdf (Page 171)

HS-21/HS-41X Handheld Reader User’s Manual A-53

Appendices

Good Read — A decode. The successful scanning and decoding of the information

encoded in a bar code symbol.

Half Duplex — A communications system in which signals can travel between devices in

both directions, but not simultaneously.

Host — A computer, PLC, or other device that is used to execute commands and process

data and discrete signals.

Image Sensor — A device that converts a visual image to an electrical signal; a CCD, for

example.

Initialize — Implement serial configuration commands into the reader’s active memory.

Input — A channel or communications line. Decoded data or a discrete signal that is

received by a device.

Ladder Orientation — A linear symbol orientation in which the bars are parallel to the

symbol’s direction of travel.

Light-Emitting Diode (LED) — A semiconductor device that emits light when conducting

current.

Lens — A transparent piece of material with curved surfaces which either converge or

diverge light rays.

Multidrop — A communications protocol for networking two or more readers or other

devices with a concentrator (or controller) and characterized by the use of individual

device addresses and the RS-485 standard.

Normally Closed — A discrete output state that is only active when open.

Normally Open — A discrete output state that is only active when closed.

Object Plane — An imaginary plane in the field of view, focused by a reader’s optical

system at the corresponding image plane on the sensor.

Output — A channel or communications line. Data or discrete signals that are transmitted

or displayed by a device.

Parity — An error detection routine in which one data bit in each character is set to 1 or 0

so that the total number of 1 bits in the data field is even or odd.

Picket Fence Orientation — A linear symbol orientation in which the bars are perpendicular

to the symbol’s direction of travel.

Pitch — Rotation of a linear or 2D symbol around an axis parallel to the symbol length on

the substrate.

See the illustration below.

Skew axis

Tilt

axis

Pitch

axis

Scan line

1 2 ... 166 167 168 169 170 171 172

Pas de commentaire

Microscan HS-2D Manuel d'utilisateur Page 171