Mitsubishi Electric MELSEC-Q Series Programming Manual page 17

■Reset step
■Types of block START steps, and their operations
• Block START step (with END check)
• Block START step (Without END check)
When a HOLD status becomes unnecessary for machine control, or on selective
branching to a manual ladder occurs after an error detection, etc., a reset request
can be designated for the HOLD step, deactivating the step in question.
• In the same manner as for a subroutine CALL-RET, a START source block
transition will not occur until the end of the START destination block is reached.
• Convenient for starting the same block several times, or to use several blocks
together, etc.
• A convenient way to return to the START source block and proceed to the next
process block when a given process is completed in a processing line, for
example.
• Even if the START destination block is active, a START source block transition
occurs when the transition condition associated with the block START step is
satisfied. At this time, the processing of the START destination block will be
continued unchanged until the end step is reached.
• By starting another block at a given step, the START destination block can be
controlled independently and asynchronously with the START source block
until processing of the current block is completed.
1 GENERAL DESCRIPTION
1.2 SFC (MELSAP-L) Features
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