Mitsubishi FX3UC Series, Руководство пользователя

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160
FX
3UC
Series Programmable Controllers
User’s Manual - Hardware Edition
5 Input Specifications and External wiring
5.5 High-speed Counters (C235 to C255)
5.5.8 Conditions for Hardware Counter to be Handled as Software Counter
The high-speed counters are classified into hardware counters and software counters.
Some hardware counters are handled as software counters depending on the operating conditions.
In this case, use hardware counters within the range of maximum response frequency and total frequency as
determined for software counters.
1. Conditions under which counters are handled as software counters
Because hardware counters execute counting at the hardware level of the FX
3UC
, they can execute counting
without regard to the total frequency.
However, under the following conditions, they are handled as software counters.
When using the counters in the condition below, the maximum response frequencies and overall frequency of
the counters are considered to be the same as those for software counters.
Hardware
counter No.
Conditions under which counters are handled as software counters
C235
C236
C237
C238
C239
C240
C244(OP)
C245(OP)
C246
C248(OP)
C251
C253
When DHSCS (FNC53), DHSCR (FNC54), DHSZ (FNC55) or DHSCT (FNC280) instruction is used
for a hardware counter number, the hardware counter is handled as a software counter.
Ex.: C235
In this case, C235 functions as a software counter.
When the index register is used for the counter number designated by DHSCS (FNC53), DHSCR
(FNC54), DHSZ (FNC55) or DHSCT (FNC280) instruction, all hardware counters are handled as
software counters.
Ex.: C235Z0
When the logic is reversed by the external rest input signal logic change function, C253 (hardware
counter) is switched to a software counter.
Ex.: The logic of the external reset input signal of C253 is inverted.
→
For the inversion of the logic of external reset input signal,
refer to Subsection 5.5.5.
DHSCS K100 C235 Y000
C235
K
DHSCS K100 C235Z0 Y000
M8388
M8389
C253
K