
Figure 7.2-2: Asynchronous Reset
Note: frame grabbers have the ability to control the LVDS input (, INPUT1-) of the
camera. This is facilitated by connecting them via two wires within the camera-framegrabber
interface cable to differential LVDS frame grabber outputs that are driven by a General Purpose
register bit that is to be controlled by host software. The TTL input (VRST_INT) is usually NOT
connected via the camera-framegrabber interface cable. Therefore, in most applications, the
VRST_INT signal floats HIGH - enabling resets from the framegrabber (under control of the host
software). In some cases, however, users may want to feed a TTL reset signal directly to the
camera, e.g. from an optical detector in an inspection application. In this case, the user must ensure
that the LVDS input (INPUT1) is either driven HIGH or allowed to float HIGH
.
In cameras that have an auxiliary input connection, the VRST_INT (TTL) input is available as one
of the pins. In some applications, this input can be used to reset the camera directly instead of
generating resets from the frame grabber.
19
INPUT 1 +
INPUT 1 –
VRST_INT (TTL)
+ 5V
VRST_INT
(TTL)
CAMERA RESET
(INTERNAL SIGNAL)
CC1+ / INPUT 1 +
(LVDS differential input from
frame grabber board)
CC1- / INPUT 1 –