Scanlab RTC6 PCIe Board - Basic Functions for Scan Head Control and Laser Control; Marking Dots, Lines and Arcs; Marking with Vector Commands and Arc Commands

RTC6 boards
Doc. Rev. 1.0.21 en-US
7 Basic Functions for Scan Head Control and Laser Control
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7 Basic Functions for Scan Head Control and Laser Control
7.1 Marking Dots, Lines and Arcs
7.1.1 Marking with
Vector Commands and
“Arc” Commands
As explained in Chapter 6.1 ”RTC6 Software Concept
Basics”, page 93, positioning of the scan system axes
(and thus of the laser beam) under RTC6 PCIe Board
control is achieved by calling:
• Jump Commands
• Mark Commands
• Arc Commands
• Ellipse Commands
Each of these commands describes one vector or
arc.
(1)
By using micro_vector[*] Commands,
arbitrarily shaped trajectories
(2)
can be implemented.
Even numeric and alphabetic characters ultimately
consist of the constituent lines, dots and arcs that
define them, see Chapter 7.5 ”Marking Dates, Times
and Serial Numbers”, page 210.
Vector Commands (Jump Commands,
Mark Commands) require as parameters the
coordinates of the end point of the corresponding
vector
(3)
. Each vector starts at the current output
position, which is the end point of the preceding
vector or arc.
“Arc” Commands (Arc Commands,
Ellipse Commands) require parameters for the
coordinates of the arc center and the arc angle(s).
Circular arcs start at the current output position. The
elliptical arc start at the position specified by the
command parameters. A direct connection to the last
output position must be explicitly ensured by the
user program itself with suitable parameters.
Otherwise, there is a “Hard Jump” there.
The output position after a RTC6 PCIe Board
Hardware Reset is the center of the Image Field, that
is, the point (0|0). Refer to Chapter 7.3 ”Scan Head
Control”, page 167 for a description of the Image
Field coordinate system.
At run-time, each vector or arc to be traced by the
scan system gets divided by the RTC6 PCIe Board into
Microsteps, see Chapter 7.1.2 ”Microstepping”,
page 140
(4)
.
Jump Commands serve to move the scan system axes
to a new position while the laser is switched off.
In contrast, Mark Commands initiate a marking
movement while the laser is switched on (see also the
following description).
(5)
To mark a point, Signals for “Laser Active” Operation
must be switched on for the desired time period after
a Jump Command or [*]mark[*] Command, see
Chapter 7.1.3 ”Marking Single Dots”, page 141.
For line and arc marking, the RTC6 PCIe Board
automatically switches Signals for “Laser Active”
Operation on at the beginning of a Mark Command
and later switches it back off (for example, at the
beginning of a subsequent Jump Command).
The synchronization of scan head control and laser
control can be adjusted by the user to the respective
application by setting delays, see Chapter 7.2 ”Delay
Settings – Coordinating Scan Head Control and Laser
Control”, page 145.
Adjustment of laser parameters is described in
Chapter 7.4 ”Laser Control”, page 184.
A thoroughly-commented example code for a basic
marking task is shown in Chapter 7.1.4 ”Example
Code (C)”, page 142.
(1) Here, wider line widths can be specified by
set_wobbel_mode.
(2) See Glossary entry on page 30.
(3) The coordinates must be specified as digital control
values (without units). To avoid confusion with
coordinates in [mm], SCANLAB uses the expression
“coordinate values [in bits]”.
(4) Only iDRIVE
scan systems (see Glossary entry on
page 27. ) which are equipped with an appropriate
tuning can execute jumps also in Jump Mode, see
Chapter 8.1.5 ”Jump Mode”, page 217.
(5) Outside a list, repositioning can be achieved by
goto_xy or goto_xyz (even while the Laser Control
Signals are on).