Omron TJ2-MC64 - PROGRAMMING Programming Manual page 293

Examples and tips
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.
5.1.6 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 signal, whether the windowing function is
used, and other options. For more information on the REGIST command,
refer to section 3.2.241.
PROGRAMMING MANUAL 287