Teledyne ProEM Series, System Manual

Page: 97 / 162

Chapter 6 Advanced Topics 97
6.3 LOGIC OUT Control
The TTL-compatible logic level output (0 to +3.3 V) from the LOGIC OUT connector on
the rear panel can be used to monitor camera status and control external devices. By
default, the logic output level is high while the action is occurring.
The timing of the level changes depends on the output type selected on the Hardware
Setup
►
Controller/Camera tab {Trigger expander}:
• Acquiring {Ready For Start}
After a start acquisition command, this output changes state on completion of
the array cleaning cycles that precede the first exposure. Initially low, it goes
high to mark the beginning of the first exposure. In free run operation it remains
high until the system is halted. If a specific number of frames have been
programmed, it remains high until all have been taken and then returns low.
Figure 6-9 assumes 3 frames have been programmed.
Figure 6-9: Comparison of READ OUT, SHUTTER, and ACQUIRING Logic Out Levels
• Expose (Effective) {Effectively Exposing}
This level is at a logic high during the effective exposure time. This exposure
time equals the read out time in frame transfer mode when the exposure time is
less than the readout time. Otherwise, Expose (Effective) and Expose
(Program'd) are identical.
• Expose (Program'd) {Exposing}
This level is at a logic high during the programmed exposure time (i.e., the time
set in the software).
• Image Shift {Shifting Under Mask}
This level is at a logic high while the image is being shifted under the mask.
• Logic 1 {Always High}
The level at the connector is high.
• Read Out {Reading Out}
It is at a logic high when CCD is being read; otherwise low.
• Shutter {Shutter Open}
This level is at a logic high while the shutter is opening and during the
programmed exposure time. The output precisely brackets shutter-open time
(exclusive of the shutter close compensation time tc) and can be used to
control an external shutter.
Acquiring
{Acquiring}
Expose 1 Expose 2 Expose 3
Expose (Program’d)
{Exposing}
Open Close Open Close Open Close
Shutter
{Shutter Open}
Read Read Read
Read Out
{Reading Out}
(Data
transferred)
(Data
transferred)
(Data
transferred)
texp to tR tc
4
4
11-
0126
_00
5
4