Welch Allyn Scanteam 3000-X2, Руководство по программному меню

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SCANTEAM 3000/PDF Information/Examples TRIGGER
Autotrigger Enable
8
Manual Trigger Enable
Note: Manual Trigger mode is not available in hand–held scanners having no trigger switch
(such as the 3000–0XC).
In autotrigger mode, the reader scans continuously. It does not, however, output decoded
messages continuously. Internal logic determines when to output a decoded message.
This decision is based on several factors, including the state of TRIGGER ON/OFF. In the
context of autotrigger mode, TRIGGER ON/OFF are defined as:
TRIGGER ON – The scanner senses the presence of several black/white elements
(does not yet know if pattern is decodable).
TRIGGER OFF – The scanner senses the lack of black/white elements.
The reader’s new autotrigger logic is aggressive, resulting in fast reads. It is not necessary
to TRIGGER OFF in order to read a new code, but in order to reread the same code, one
needs to TRIGGER OFF for about a quarter of a second.
In manual trigger mode, a TRIGGER ON is required to activate scanning and decoding. In
the context of manual trigger mode, TRIGGER ON/OFF are defined as:
TRIGGER ON – (A) The trigger switch is pressed
or (B) The serial TRIGGER ON
command (ASCII 18 decimal) is sent to the reader.
TRIGGER OFF – (A) The trigger switch is released or (B) The serial TRIGGER OFF
command (ASCII 20 decimal) is sent to the reader.
In manual trigger mode it is necessary to TRIGGER OFF following a successful decode
before another code can be read. The scanning stops immediately following a successful
decode, but the reader is not TRIGGERED OFF until one of the conditions above has been
satisfied.
A power–saving mode is available for hand–held readers having a hardware trigger in
manual trigger mode. All that is required is the proper cable. (Contact your sales
representative or refer to the IPWC Cable Matrix for hand–held CCD
constant/switched–power cable information.) On power–up, the reader senses if the
unit is using the switched–power cable, and goes immediately into a low–power mode.
Only the trigger–sensing circuitry is powered (current draw is
0.23 mA @ 5V for
3000–12C) until the trigger is pulled. Refer to the scanner’s Technical Manual for specifics.
Generally, a TRIGGER ON causes the reader to begin decoding, and a TRIGGER OFF
halts decoding. The meaning of TRIGGER ON and TRIGGER OFF depends on the trigger
mode.
Note: If the scanner is triggered serially, it isn’t necessary to send the TRIGGER OFF
command.