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AW00123404000 Physical Interface
Basler ace USB 3.0 69
5.10 Temporal Performance of I/O Lines
This section describes delays ("propagation delays") resulting from the operation of the camera’s
input and output lines. For image acquisition, the propagation delays must be added to the delays
described in Section 6 on
page 97 .
You will need the information included in this section most likely only if you need microsecond
accuracy when controlling camera operation via I/O lines.
All examples in this section assume that the I/O line inverters are disabled.
5.10.1 Introduction
As indicated in Section 5.2 on page 52 , the camera provides two different kinds of I/O lines:

opto-isolated I/O lines

direct-coupled General Purpose I/O (GPIO) lines.
The related electrical characteristics and circuit schematics are given in Section 5.7 through
Section 5.9 .
With regard to use, the two kinds of I/O lines differ mainly in these respects:

The opto-isolated I/O lines have the advantage of being distinctly more robust against EMI
than the GPIO lines.

The propagation delays ("response times") differ between the two kinds of I/O lines.
A propagation delay is the time that elapses between the moment when a signal voltage passes
through the transition threshold and the moment when the related line status changes – or vice
versa (see
Figure 41 for camera input and Figure 42 for camera output).
The following important characteristics are apparent from Figure 41 and Figure 42 :

The propagation delays for the opto-isolated I/O lines are in most cases longer than for the
GPIO lines. In other words, the opto-isolated I/O lines are usually "slower" than the GPIO lines.

For each analog signal, the rising edge and the falling edge are associated with different
propagation delays. The edge with the shorter propagation delay (the "fast" edge) is indicated
by an asterisk.