Mitsubishi Electric RD62P2E Application User's Manual page 21

■When the count range is Present value < Ring counter lower limit value or Ring counter upper
limit value < Present value
• When pulses are counted up, even when the present value reaches the ring counter lower limit value, the ring counter
lower limit value is held as the lower limit, and the value of Ring counter upper limit value + 1 is stored in CH1 Present value
(Un\G2 to Un\G3) at the next count-up pulse input.
• When pulses are counted down, the ring counter lower limit value is automatically stored in CH1 Present value (Un\G2 to
Un\G3) when the present value reaches the ring counter upper limit value.
Both when pulses are counted up and when pulses are counted down, the ring counter upper limit value is not stored in CH1
Present value (Un\G2 to Un\G3). For example, when the count enable command is valid while the ring counter lower limit
value is 0, the ring counter upper limit value is 2000, and the present value is 3000, the count range and the present value will
change as follows.
-2147483648
Counting range
Present value
to
3000 3001 2147483647 -2147483648
■When the count range is Ring counter lower limit value = Ring counter upper limit value
When this condition is established, a value that can be expressed in 32-bit signed binary (-2147483648 to 2147483647) will
be the count range, regardless or the present value.
• While CH1 Count enable command (Y4) is on, even if CH1 Ring counter lower limit value setting (Un\G20 to
Un\G21) and CH1 Ring counter upper limit value setting (Un\G22 to Un\G23) are changed, the high-speed
counter module does not operate with the changed value. Turn off CH1 Count enable command (Y4) before
changing the ring counter upper limit value or ring counter lower limit value.
• Turn off CH1 Count enable command (Y4) before changing the count range using the preset function.
Ring counter Ring counter
lower limit value upper limit value
0
2000
Present value
3000
Counting range
Ring counter Ring counter
upper limit value lower limit value
(2000)
to
-2 -1 0 2001
The ring counter upper limit
value, 2000, is not stored in CH1
Present value (Un\G2 to Un\G3).
2147483647
to
2002 2998 2999
1 FUNCTIONS
1.2 Selecting a Counter Type
1
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