IDEC FT1A Series User Manual page 115

Timing chart 2
Two-phase high-speed counter (group 1) timing chart
Operating conditions
The counting mode is set to 2-edge count and reset input (I2) is used.
Two preset values are used, and when preset value 1 matches, output Q1 turns on and the current value is kept.
When preset value 2 matches, output Q2 turns on and the current value is cleared.
Overflow and underflow are not used.
Current value
14
Preset value 2=14
13
12
11
10
Preset value 1=8
Reset value=4
(D8554, D8555)
A-phase I0
B-phase I1
Reset input I2
Reset status M8033
Gate input M8031
Preset value
M8034
Comparison ON status
Preset value 1
Q1
Comparison output
Preset value 2
Q2
Comparison output
Comparison output
M8030
reset
When reset input (I2) turns on, the reset value (D8054, D8055) is stored in the current value (D8050, D8051).
1.
In this situation, reset status (M8033) turns on for only one scan.
When gate input (M8031) turns on, the counting begins.
2.
When the A-phase pulse (I0) precedes the B-phase pulse (I1), the count goes up. When the B-phase pulse (I1) precedes the
3.
A-phase pulse (I0), the count goes down.
When the current value and preset value 1 (D8052, D8053) match, the preset value 1 comparison output (Q1) and setting
4.
value match (M8034) turn on.
When preset value 1 matches, preset value 2 is stored in the preset value (D8052, D8053) as the new preset value and
counting continues.
The preset value 1 comparison output (Q1) maintains the on state until comparison output reset (M8030) turns on. M8034
5.
turns on for only one scan.
9
8
7
6
5
4
3
2
1
0
1
1
UP
One scan
One scan
S AXIS P
MART RO
One scan
Reset
/L U ' M FT9Y-B1378
ITE SER S ANUAL
5: S
PECIAL
1
0
DOWN
Reset
F
UNCTIONS
5-27