Examples and tips
PROGRAMMING MANUAL
259
Revi
si
on 3.0
Static origin search, forcing a position from an absolute
encoder
This origin search procedure sets the actual position to the position
of an absolute encoder. It does not perform any physical move. It is
only possible with an axis with an absolute encoder in a control
loop.
6.1.6
Registration
Registration, also called ‘latch’ or ‘print registration’, is about real-
time storing of the position of an axis when an external input is
activated. The information that is registered, i.e. stored, is
processed later, not in real time, by the application program.
Registration is different from processing an interrupt input or signal.
With registration, no event is generated when the registration input
is activated. Also, the normal execution of the application program
is not disturbed or interrupted. Only the position of an axis is stored.
This information can be used, like other parameters or values, in a
program. The registration information is available to a program
immediately after the registration.
The advantage of registration is that it is done very quickly.
Therefore, the axis position that is stored is very accurate. To
achieve this speed and accuracy, registration is implemented with
hardware, and the registration input must be on the same board as
the encoder input that provides information on the axis position.
Capturing and storing the axis position is done in real time by the
hardware. Processing this information is done not in real time by
the application program.
The REGIST axis command
In Trajexia, you do a registration with the
REGIST
axis command.
This command takes one argument. This argument determines
which external input is registered, whether the registration is
executed on the rising edge or on the falling edge of the input
I52E-EN-03.book Seite 259 Freitag, 29. Juni 2007 11:55 11