NOVA electronics Inc.
MCX514 -
35
－
35
－
0
+10000
-1000
SP
SM
＋
direction software limit error
Current position
≧
SP
－
direction software limit error
Current position
＜
SM
SLMT+ register SP=10000
SLMT- register SM=-1000
Fig. 2.3-2 Value Setting of Software Limit and Software Limit Error
Software limit function can be enabled /disabled by setting D13 bit of WR2 register. And there are two stop types of software limit,
decelerating stop and instant stop, which sets D15 bit of WR2 register. SLMT+ and SLMT
− registers can be written anytime.
Software limit function will be disabled and the values of SLMT+ and SLMT
− registers will be undefined at reset.
2.3.4
Position Counter Variable Ring
A logical position counter and a real position counter are 32-bit up/down ring counters. Therefore, normally, when the counter
value is incremented in the + direction from FFFF FFFFh which is the maximum value of the 32-bit length, the value is reset to 0.
When the counter value is decremented in the − direction from 0, the value is reset to FFFF FFFFh. The variable ring function
enables the setting of any value as the maximum value. This function is useful for managing the position of the axis in circular
motions that return to the home position after one rotation, rather than linear motions.
The variable ring size, that is the maximum value of the logical / real position counter can be set to any value within the range of
1~2,147,483,647 (1~7FFF FFFFh). To use the variable ring function, set the logical position counter maximum value (LX) by
logical position counter maximum value setting command (0Eh) and set the real position counter maximum value (RX) by real
position counter maximum value setting command (0Fh).
The value of the logical position counter maximum value (LX) and real position counter maximum value (RX) will be FFFF
FFFFh at reset. When not using the variable ring function, leave it at default.
■
Example of Variable Ring Setting
For instance, set as follows for a rotation axis that rotates one cycle with 10,000 pulses.
①
Set 9,999 (270Fh) in the logical position counter maximum value (LX).
②
Set 9,999 (270Fh) in the real position counter maximum value (RX) also if using a real position counter.
The count operation will be as follows.
・
Increment in the + direction
：
…→
9998→9999→0→1→…
・
Decrement in the
− direction
：
…→
1→0→9999→9998→…
0
9999
＋
－
5000
1
9998
2
Fig. 2.3-3 Operation of Position Counter Ring Maximum Value 9999
[Note]
•
It is possible to set the value within the range of 1~2,147,483,647 (1~7FFF FFFFh) as the maximum value of the
variable ring function. The signed negative value (8000 0000h
～
FFFF FFFEh) of a 32-bit register cannot be set.
•
When setting values to the logical position counter (LP) and real position counter (RP), the values out of the range of
the logical position counter maximum value (LX) and the real position counter maximum value (RX) cannot be set.
