Response Frequency Of High-Speed Counters - Mitsubishi FX3G Series Programming Manual

FX /FX /FX /FX
3G 3U 3GC 3UC
Programming Manual - Basic & Applied Instruction Edition
4.7.10

Response frequency of high-speed counters

1. Response frequency of hardware counters
The table below shows the maximum response frequency of hardware counters.
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 some times subject to
restrictions in total frequency.
Counter type
1-phase 1-counting input
1-phase 2-counting input
2-phase 2-counting
input
2. Response frequency and total frequency of software counters
The table below shows the maximum response frequency and total frequency of software counters.
When using the HSZ or HSCT instruction in a program, both the maximum response frequency and the total frequency
are limited for all software counters without regarding the operands of the instruction. When examining a system or
creating a program, consider the limitations, and use software counters within the allowable range of maximum
response frequency and total frequency.
1) When special analog adapters and FX
Software
Counter type
counter
C241,
C242, C235, C236,
C243, C237, C238,
1-phase
C244, C239, C240
1-counting
C245
input
C244(OP),
−
C245(OP)
1-phase C247,
C246,
2-counting C248,
C248(OP)
input C249, C250
1 edge
2-
count C252,
phase
C253(OP),
2-
C251, C253
count-
C254,
4 edge
ing
C255
count
input
*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) can count up to 10 kHz.
112
Series
→ For the conditions in which hardware counters are handled as software counters,
C235, C236, C237, C238, C239, C240
C244(OP), C245(OP)
C246, C248(OP)
1 edge count
C251, C253
4 edge count
→ For the conditions handled as software counters, refer to the previous page.
When HSZ and HSCT
Magnifica-
Following
instructions are not
tion for
software
calculating
counter with
total Maximum
HSCS, HSCR,
frequency response
HSZ or HSCT
frequency
*1
instruction
(kHz)
×1
40
×1
10
×1
40
×1
40
×4
10
Counter No.
/FX Series special function blocks/units are not used
3U 3UC
Response frequency and total frequency according to instructions used
When only HSCT
instruction is used
used
Maximum
Total Total
response
frequency frequency
frequency
(kHz) (kHz)
(kHz)
30
10
80
30
30
7.5
4.7 High-Speed Counter [C] (FX3U/FX3UC PLC)
refer to the previous page.
Maximum response frequency
Main unit
100 kHz
10 kHz
100 kHz
50 kHz
50 kHz
When only HSZ
instruction is used
Maximum
Total
response
frequency
frequency
(kHz)
(kHz)
40 - (Num-
ber of
80−
instruc-
1.5×(Num
*2
tion)
60 ber of
instruc-
tion)
(40-Num-
ber of
instruc-
tion) ÷ 4
4 Devices in Detail
FX -4HSX-ADP
3U
200 kHz
100 kHz
100 kHz
When both HSZ and HSCT
instructions are used
Maximum
Total
response
frequency
frequency
(kHz)
(kHz)
30-(Number
of instruc-
60−
*2
tion)
1.5×(Num
ber of
instruc-
tion)
(30-Number
of instruc-
tion) ÷ 4