Mitsubishi Electronics FX3G User Manual

Page of 964
102
FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
 Series
Programming Manual - Basic & Applied Instruction Edition
4 Devices in Detail
4.6 Counter [C]
4.6
Counter [C]
4.6.1
Numbers of counters
The table below shows counter (C) numbers. (Numbers are assigned in decimal.)
1. FX
3S
 PLC
→ For high-speed counters, refer to Section 4.7.
2. FX
3G
/FX
3GC
 PLCs
→ For high-speed counters, refer to Section 4.7.
3. FX
3U
/FX
3UC
 PLCs
→ For high-speed counters, refer to Section 4.8.
*1.
This area is not latched (battery backed). It can be changed to a latched (battery backed) area by setting the
parameters.
*2.
This area is latched (battery backed). It can be changed to a non-latched (non-battery-backed) area by setting
the parameters.
Counter numbers not used as counters can be converted as data registers for storing numeric values.
4.6.2
Features of counters
The table below shows the features of 16-bit counters and 32-bit counters. They can be used in accordance with the
operating condition such as the counting direction switching and counting range, etc.
16-bit up counter 
Counting range: 0 to 32767
32-bit bi-directional counter 
Counting range: 
2,147,483,648 to +2,147,483,647 
General type
Fixed latched (EEPROM keep) type
General type
C0 to C15
16 points
C16 to C31
16 points
C200 to C234
35 points
16-bit up counter 
Counting range: 0 to 32767
32-bit bi-directional counter 
Counting range: 
2,147,483,648 to +2,147,483,647 
General type
Fixed latched (EEPROM keep) type
General type
Fixed latched (EEPROM keep) type
C0 to C15
16 points
C16 to C199
184 points
C200 to C219
20 points
C220 to C234
15 points
16-bit up counter 
Counting range: 0 to 32767
32-bit bi-directional counter 
Counting range: 
2,147,483,648 to +2,147,483,647 
General type
Latched (battery backed)
type (protected by battery against 
power failure)
General type
Latched (battery backed)
type (protected by battery against 
power failure)
C0 to C99
100 points
*1
C100 to C199
100 points
*2
C200 to C219
20 points
*1
C220 to C234
15 points
*2
Item
16-bit counter
32-bit counter
Counting direction
Up-counting
Up-counting and down-counting can be switched (as
shown in Subsection 4.6.3)
Set value
1 to 32767
−2,147,483,648 to +2,147,483,647
Set value specification
Constant (K) or data register
Constant (K) or a pair of data registers
Current value change
Does not change after counting up
Changes even after counting up (ring counter)
Output contact
Latches after counting up
Latches (in up-counting), or reset (in down-counting)
Reset operation
When RST instruction is executed, current value of counter is reset to "0" and output contact returns
Current value register
16 bits
32 bits