Mitsubishi FX3UC Series, Руководство пользователя

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161
FX
3UC
Series Programmable Controllers
User’s Manual - Hardware Edition
5 Input Specifications and External wiring
5.5 High-speed Counters (C235 to C255)
1
O
utline
2
Exter
nal
D
im
en
sions
3
Ge
ne
ric
Speci
ficat
ions
4
Pow
er Suppl
y
Specif
icati
ons
5
Input Spec
ific
ations
6
O
utput
Specif
icat
ions
7
Exam
pl
es
of
W
iri
ng
fo
r
Va
rious U
ses
8
Te
rm
inal B
lock
9
CC
-L
in
k/L
T
Ma
ste
r F
X
3UC
(LT
only)
10
D
ispl
ay m
odule
FX
3UC
(L
T only)
5.5.9 Calculation of Response Frequency and Overall Frequency
Response frequencies of hardware counters
The maximum response frequencies of the hardware counters are shown in the following table.
When hardware counters are handled as software counters in some operating conditions, their maximum
response frequency becomes equivalent to that of software counters, and thus hardware counters are
sometimes subject to restrictions in total frequency.
→
For the conditions under which the hardware counters are handled as software counters,
refer to the previous page.
Response frequencies and overall frequency of software counters
The maximum response frequencies and overall frequency of software counters are shown below.
When HSZ or HSCT instruction is used in the program, limitations are placed on the maximum response
frequencies and overall frequency of all software counters regardless of the instruction operand.
When examining a system or creating a program, consider the frequency limitations and use the software
counters within their allowable ranges.
1. When FX
3U
/FX
3UC
Series special function blocks and analog special adapters are not used
Examples of calculation are given in the heavy-line frame.
*1. When an index register is added to a counter number specified by a HSCS, HSCR, HSZ or HSCT
instruction, all hardware counters are switched to software counters.
*2. The high-speed counters C244 (OP) and C245 (OP) cannot count signals of 10kHz or more.
Counter type Counter Nos. Max. response frequency
1-phase 1-count input
C235, C236, C237, C238, C239, C240 100kHz
C244(OP), C245(OP) 10kHz
1-phase 2-count input C246, C248 (OP) 100kHz
2-phase 2-count
input
1 edge count
C251, C253
50kHz
4 edge count 50kHz
Counter
type
Software
counter
Nos.
Software
counters
with HSCS,
HSCR, HSZ
or HSCT
instruction
*1
Magni-
fication
for
calcu-
lation
of
overall
frequ-
ency
Response frequency and overall frequency depending
on instructions being used
Neither HSZ nor
HSCT instruction
Only HSCT
instruction
Only HSZ instruction
Both HSZ and HSCT
instructions
Max.
response
frequency
(kHz)
Overall
frequency
(kHz)
Max.
response
frequency
(kHz)
Overall
frequency
(kHz)
Max.
response
frequency
(kHz)
Overall
frequency
(kHz)
Max.
response
frequency
(kHz)
Overall
frequency
(kHz)
1-phase
1-count
input
C241
C242
C243
C244
C245
C235
C236
C237
C238
C239
C240
×
1 40
80
30
60
40 -
(number of
instruc-
tion)
*2
80 - 1.5
×
(number of
instruc-
tion)
30 -
(number of
instruc-
tion)
*2
60 - 1.5
×
(number of
instruc-
tion)
−
C244 (OP)
C245 (OP)
×
1 10 10
1-phase
2-count
input
C247
C248
C249
C250
C246
C248 (OP)
×
1 40 30
2-
phase
2-
count
input
1
edge
count
C252
C253
(OP)
C254
C255
C251
C253
×
1
40 30
4
edge
count
×
4 10 7.5
(40 -
number of
instruc-
tion) / 4
(30 -
number of
instruc-
tion) / 4