RTC
®
5 PC Interface Board
Rev. 1.9 e
6 Developing User Applications
61
innovators for industry
6
Developing User Applications
6.1 RTC
®
5 Software Basics
6.1.1 Controlling Scan Systems and
Lasers – An Introductory
Example
SCANLAB’s RTC
®
5 PC interface board and its related
software are designed for controlling scan systems
and lasers. To illustrate the principle of operation,
shows a simple laser marking sample
(1)
.
The image is made up of straight line segments
(vectors) and arc segments. The RTC
®
5 software
driver provides a set of jump, mark, arc and ellipse
commands for laser processing along such segments.
Each of these commands describes one vector or arc.
Additional software commands are available for
controlling the laser during the marking process.
The RTC
®
5 processes the commands it receives and
precisely transmits the required marking signals to
the scan head (using a pre-defined 10
µ
s time raster)
and to the laser. The scan head’s galvanometer
scanners accurately position their deflection mirrors
in synchronization with the incoming control signals.
Appropriate RTC
®
5 commands also allow querying of
the current scan head status information.
For laser control, the RTC
®
5 provides various analog
and digital signal outputs freely available for tailoring
laser control to customer-specific requirements. The
customer assumes responsibility for use of these
signals.
6.1.2 List Commands and
Control Commands
The RTC
®
5 command set consists of
control commands
and
list commands
.
Control commands
are executed immediately.
They are used, for instance, for initializing,
controlling execution of lists, setting some general
parameters, or for directly controlling the laser and
scan head.
Before a
list command
can be sent to the RTC
®
5, a
control command must define the input pointer to
which subsequent list commands will be transferred
(this corresponds to opening a list, see
). List commands sent to the RTC
®
5
afterwards are not executed immediately, but stored
in a list buffer. The RTC
®
5 begins reading the
commands from the list buffer and processing them
in real time only after the list is started.
Some list commands, which are called short list
commands, don’t require the full 10
µ
s clock period
for command execution - instead, they execute along
with the next list command, one directly after the
other within a single 10
µ
s clock period, during which
control commands cannot execute. The total list
processing time is thereby reduced.
List commands include jump commands,
mark commands and arc commands, as well as
commands for setting various scanning parameters
such as laser power, jump speed and marking speed.
Short list commands include
etc. With polygon traversals (polylines), for example,
the laser power can be set individually for each vector
via the short list command
without
interrupting traversal of the polygon (the laser
remains on).
Some commands exist in two versions: as a list
command and as a control command. Among these
dual-version commands are the I/O commands.
All RTC
®
5 commands are described in detail
in
chapter 10 "Commands And Functions"
.
An overview is provided in
.
(1) In this manual, laser marking is mentioned only as an example
of the many possible laser materials processing applications.
Mark
M
ark
M
ark
Mark
A
rc
Mark
Mark
M
ar
k
Mark
Jum
p
Ju
m
p
Ju
m
p
Jump
Ju
mp
Jum
p
Mark
A
rc
Mark
El
lip
se
26
A laser marking sample
