IDEC microsmart pentra, Programming Manual

Page: 62 / 344

5: B
ASIC
I
NSTRUCTIONS
5-16 FT1A S
MART
A
XIS
U
SER
’
S
M
ANUAL
FT9Y-B1382
CDPD (Double-Word Dual-Pulse Reversible Counter)
The double-word dual-pulse reversible counter CDPD has up and down pulse inputs, so the three inputs are required. The circuit
for a double-word dual-pulse reversible counter must be programmed in the following order: preset input, up-pulse input, down-
pulse input, the CDPD instruction, and a counter number C0 through C198, followed by a counter preset value from 0 to
4,294,967,295.
The preset value can be designated using a constant or a data register. When a data register is used, the double-word data of two
consecutive data registers becomes the preset value. For 32-bit data storage setting, see page 5-48.
 Double-word counter instructions use two
consecutive counters, and counters cannot be used
more than once in a user program.

The preset input must be turned on initially so that
the current value returns to the preset value.

The preset input must be turned off before counting
may begin.

When the up and down pulses are on simultaneously,
no pulse is counted.

The counter output is on only when the current value
is 0.

After the current value reaches 0 (counting down), it
changes to 4,294,967,295 on the next count down.

After the current value reaches 4,294,967,295
(counting up), it changes to 0 on the next count up.

When power is off, the counter’s current value is
held, and can also be designated as “clear” type
counters using the Function Area Settings (see page
5-5).

Counter preset and current values can be changed
using WindLDR without downloading the entire
program to the CPU again. From the WindLDR menu
bar, select
Online > Monitor > Monitor , then
Online > Custom > New Custom Monitor . To
change a counter preset value, select DEC(D) in the
pull-down list box.
 When the preset or current value is changed during
counter operation, the change becomes effective
immediately.

When power is off, the changed preset values are
cleared and the original preset values are loaded.

For the data movement when changing, confirming,
and clearing preset values, see page 5-18.

WindLDR ladder diagrams show CP (counter preset
value) and CC (counter current value) in advanced
instruction devices.
100000 100000
Ladder Diagram
Preset Input I0
ON
OFF
Up Pulse I1
ON
OFF
Down Pulse I2
ON
OFF
Timing Chart
Counter C2
ON
OFF
100000 100001
Counter C2 Value
100000
0 1
• • •
• • •
I0
I1
CDPD C2
100000
I2
Preset Input
Up Pulse
Down Pulse
I3 C2 Q1
99999
LOD
LOD
LOD
CDPD
LOD
AND
OUT
Program List
Instruction Data
I0
I1
I2
C2
100000
I3
C2
Q1