Yaskawa MP2200 Machine Controller User Manual
Page 408

7 Absolute Position Detection
7.3.2 Infinite Length Axis
7-24
( 6 ) Ladder Program for Infinite Length Axis Position Control
Ladder program for normal operation and for restarting the system is needed for absolute infinite
length axis position control when the simple absolute infinite length position control function is not
used.
[ a ] Normal Operation
1.
Check the status of the Zero Point Return (Setting) Completed bit.
Check to see if the Zero Point Return (Setting) Completed bit (monitoring parameter
IW0C, bit 5) is ON. If it is, go to step 2. If it is not, it means that the pulse position at power
OFF, encoder position at power OFF and all position data was not settled. In that case, restart
the system and set up the position data again or execute the ZSET (zero point setting) motion
command to settle the position data all over from the start.
2.
Save the modularized position at power OFF and absolute position at power OFF.
Use the ladder program to save the following monitoring parameters with high-speed scan
timing at an M register backed up by battery.
• Monitoring Parameter: Absolute Position at Power OFF (All four words at IL5E to
IL60)
• Monitoring Parameter: Modularized Position at Power OFF (All four words at IL62 to
IL64)
The M register that is used to save the above monitoring parameters is structured as shown
below.
(
Note)Two buffers are needed to save the absolute position and the modularized
position at power OFF because the program may be exited without settling
position data at all four words if power is turned OFF during the high-speed
scan.
MW
Bit 0
Toggle Buffer Enabled Flag (OFF: Disabled, ON: Enabled)
Bit 1
Toggle Buffer Selection Flag (OFF: Buffer 0, ON: Buffer 1)
Bit 2
Position Data Re-setup Request Flag (OFF: Complete, ON: Request)
MW +1
Not used
ML +2
ML +4
Buffer 0
Monitoring Parameter:
Absolute Position at
Power OFF
Lower-place two words
(IL5E
)
Upper-place two words
(IL60
)
ML +6
ML +8
Monitoring Parameter:
Modularized Position at
Power OFF
Lower-place two words
(IL62
)
Upper-place two words
(IL64
)
ML +10
ML +12
Buffer 1
Monitoring Parameter:
Absolute Position at
Power OFF
Lower-place two words
(IL5E
)
Upper-place two words
(IL60
)
ML +14
ML +16
Monitoring Parameter:
Modularized Position at
Power OFF
Lower-place two words
(IL62
)
Upper-place two words
(IL64
)