Developers guide

Chapter 14: Scanners
Controlling A Bar Code Scan
Psion Teklogix Mobile Devices SDK Developers Guide 151
14.4.2 Controlling A Bar Code Scan
The following timing parameters control bar code scanning for the internal scanner:
Double-click time
This parameter defines the time within which the scanner trigger must be pressed twice, if the
trigger presses are to be interpreted as a double-click and not as two single-clicks. The following
setting controls this for the internal scanner and an external non-decoded scanner:
• Scs\Click Time: see “Configuring Scanner Properties” on page 90
for details.
Dot time
For scanners with an aiming dot, this parameter defines the length of time for which the aiming
dot is enabled before scanning begins. The following settings control this:
• Non-decoded\Dot Time; see “Non-decoded Scanner Options” on page 92
for details.
• Decoded\Aiming Mode; see “Decoded Scanner Options” on page 92
for details.
• Imager\Dot Time; see “Imager Options (Deprecated)” on page 94
for details.
Scan beam on time
This parameter defines the maximum length of time that the scanning beam is enabled. This can
only be set for decoded scanners using the following parameter:
• Decoded\Laser On Time; see “Decoded Scanner Options” on page 92
for details.
The only way that the scanning beam can be turned off before the end of this time is by releasing
the scanner trigger.
The following diagram shows the timing sequence for an operator controlled bar code scan:
Figure 14.1 Operator Controlled Scanner Timing Sequence
Double click time Dot time
Scan beam on time
Typically 250 msec. Typically 2.5 sec. Typically 5 sec.
Time
Scanner trigger pressed
Scan initiated
Double click time Dot time
Scan beam on time
Typically 250 msec. Typically 2.5 sec. Typically 5 sec.
Time
Scanner trigger pressed
Scan initiated