Yaskawa YASNAC PC NC PLC Programming Manual - Manual (Page 88)

6 - 52
YASNAC PCNC PLC Programming Manual Chapter 6: PLC Instructions
• Reset (RST)
RST = 0: Reset released
RST = 1: Reset
R1 is cleared to “0”.
Counted value is reset to the initial value.
• Count signal (ACT)
ACT = 0: The counter does not operate. Contents of R1 remain unchanged.
ACT = 1: Counts at the rising edge (“0”
Å “1”)
If the content of the counter is greater than the preset value, the counter operates
in the following manner.
UP counter: The value returns t the initial value at the first ACT signal.
DOWN counter: The value is reduced at each input of ACT until the count values
is reduced to the preset value. After that the counter operates as
a normal counter.
• Count-up output (R1)
UP counter: “1” is set for R1 upon counting up to the preset value.
DOWN counter: “1” is set for R1 according to the following condition.
CNO = 0: Upon counting down to “0”.
CNO = 1: Upon counting down to “1”.
(4) SUBP 006 (ROTATION) RR after operation:
Ù
(a) Function
This instruction is used to control rotating units such as turrets, ATCs, and rotary tables.
It has the following functions:
• Determination for shorter-path when determining the direction of rotation.
• Calculation of the number of steps between the present position and the target
position.
• Calculation of the position one step before the target position or the number of steps to
the position one step before the target position.