Free Run - Basler A500k User Manual

Basic Operation and Features

3.2.2 Free Run

In free-run, no ExSync signal is required. The camera generates a continuous internal control
signal.
When the camera is operating in free-run, it exposes and outputs frames continuously.
cameras have a free-run, programmable mode. The A504
k
A500
free-run, VGA mode.
• In free-run, programmable mode, the camera generates a continuous internal control sig-
nal based on two programmable parameters: "Timer 1" and "Timer 2." Timer 1 determines
how long the internal control signal will remain low and Timer 2 determines how long the sig-
nal will remain high. Pixels are exposed and charge is accumulated when the internal control
signal is low. The length of the control signal period determines the camera's frame rate. The
control signal period is equal to Timer 1 plus Timer 2. The frame is read out and transferred
on the rising edge of the internal control signal. See Figure 3-7.
In this mode, the exposure time can programmed as desired by varying the setting of the
"Timer 1" parameter.
Internal
Control
Signal
Figure 3-7: Free-run, Programmable Mode

3-6
PRELIMINARY
Control Signal Period
Timer 1
Exposure
In the free-run programmable mode, the period of the internal control signal is
equal to the sum of Timer 1 plus Timer 2. The sum of the Timer 1 setting plus the
Timer 2 setting must be greater than the maximum frame rate.
The minimum exposure time is 10 µs.
cameras additionally have a
k
Timer 2
Frame Readout
k
Basler A500