where reproducibility and accuracy are essential. To use power regulation, a desired power reference
value in milliwatts is entered in the onboard control GUI (Figure 5, Control tab [left]). To activate
power regulation, simply click the padlock icon next to the reference power value (Figure 5, Control
Tab (Left), 5). Gray shading of the padlock icon and the reference power value shows that power
regulation is active for the selected output channel. When power regulation is active, the intensity
setting for the channel is controlled by the onboard microprocessor, based on feedback from the
light engine’s reference photodiode array. The microprocessor continuously adjusts the intensity
setting so that the output power matches the power reference value set by the user.
3.3.4 Control via Serial ports
RETRA (L) Light Engines have two serial ports, labeled USB and RS-232 (Figure 3), which can be set
to receive either LEGACY or STANDARD mode commands. Connection to the computer requires a
USB-A-to-USB B cable (29-10058) or USB-to-RS-232 cable
(29-10011). LEGACY commands are limited to controlling on/o
ff
switching and intensity adjustment of individual color channels. Only
one of the two ports can be set to LEGACY mode at one time. The
STANDARD mode command set gives access to an extensive panel of
operating status reports and configuration settings in addition to the
the basic control functions of the LEGACY command set. A complete
listing of STANDARD mode commands is provided in
Lumencor Light
Engine Command Reference
(Document number 57-10018). Note that
LEGACY and STANDARD mode communications use di
ff
erent serial
protocols (9600,8,N,1 and 115200,8,N,1 respectively). Changes to the
command mode setting for a serial port can be made via the
Settings
screen of Web GUI (Figure 5, right). Changes are applied
instantaneously and are retained between power cycles.
Select the command mode setting for the serial port that is compatible
with the light engine device driver in the control software. This
selection is typically found under the “Devices” tab. The COM port
address assigned by the computer to the light engine USB serial port
must be correctly registered in control software.
3.3.5 Control Light Engine Control Pod
1. Connect the RETRA (L) Light Engine to pod using USB A-to-USB B
cable (29-10058).
2. Open the Web GUI control interface as described in Section 3.3.2.
RETRA (L) Light Engine Manual 57-10025
15
lumencor.com
Figure 6
. BNC breakout cable to
enable TTL triggering
TTL Connector Pin Definitions
OUTPUT
COLOR
Pin
#
OUTPUT
COLOR
Pin
#
RED
1
BLUE
12
GREEN
2
VIOLET
13
CYAN
3
nIR
14
TEAL
11
YELLOW 15
Gnd
6,7,8,10
V
ihigh
(min) = 2.0V, V
ihigh
(max) = 5.5V
V
ilow
(min) = 0.0V, V
ilow
(max) = 0.8V
