Omron trajexia CJ1W-MCH72 Operation Manual page 316

How-to's
5-1-5-5 Static origin search, forcing a position from a user reference
5-1-5-6 Static origin search, forcing a position from an absolute encoder
5-1-6 Registration
This origin search procedure performs origin search by searching for the "Zero
Mark" signal of the encoder. This signal is also known as "marker" or
"reference pulse". It appears one time per full encoder revolution. The
example for this homing procedure is shown in the figure.
REVERSE
The possible scenarios for origin search using encoder reference pulse "Zero
Mark", depending on the position of the moving part on power on, are shown
in the figure.
The program example that does this origin search sequence is given below.
'Origin and left limit switch: IN0
'Right limit switch: IN1
REV_IN=-1
BASE(0)
DATUM_IN=0
SERVO=ON
WDOG=ON
DATUM(6)
WA(1)
WAIT IDLE
This origin search procedure performs a static origin search by directly forcing
an actual position. It does not perform any physical move.
DATUM(0)
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.
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
encoder 2 pulses
FORWARD
Section 5-1
min limit switch
max limit switch
305