Yaskawa MP2000 - Manual (Page 68)

TECHNICAL NOTE
LATCH function
Function block for MP2000 series
<LATCH> Function Block Summary
The LATCH function block enables the high speed latch for a motor axis encoder. This block should be
used any time the high-speed latch is required except when the Latch Target (Index Move) block is used.
Function Block Diagram
<LATCH> Function Block Operation notes
• Rising edge of EXECUTE input initiates block operation, and the following block
input values are read once: AXIS.
• To use the function block, the EXECUTE bit must be held ON. During this, the
STATE bit is constantly monitored (STATE indicates latch request from user).
• The
RUNNING
output bit will be held high until a latch is received, EXECUTE
goes low, or an Error occurs. The block will continue to monitor the axis for errors
as long as the EXECUTE input stays True.
• If it is EXECUTE=High, and STATE=High, the controller arms latch detection,
and wait for the signal specified in the LTSEL be ON. DONE output bit becomes
High when latch detection is completed. Latched data of the machine coordinate
system is stored to IL**18.
• Latch speed is 30microsec or less.
• Latch detection signal is “/EXT1" if LTSEL=1 and SGDS-***12A (with M ) servo
amplifier parameter is default. Input of latch sensor connected with SGDS 1CN
connector pin10 can be monitored at IB**2E6
• The latch detection signal is selected by setting LTSEL. 0= C phase pulse, 1=/
EXT1, 2=/ EXT2 and 3=/ EXT3
• Five words are used as working registers for this function, starting at the address
in Data05W.
File: MP2000_IndividualFunctionDocument_RevC 68/168
Doc Number: eng.MCD.05.101
11/17/2005