Cntd, Cdpd, And Cudd (Double-Word Counter) - IDEC MICROSmart FC6A Series Ladder Programming Manual

4: B I
ASIC NSTRUCTIONS

CNTD, CDPD, and CUDD (Double-Word Counter)

Three types of double-word counters are available; adding (up) counter CNTD, dual-pulse reversible counter CDPD, and up/down
selection reversible counter CUDD. A total of 256 double-word counters can be programmed in a user program. Each double-word
counter uses 2 consecutive devices starting with the allocated device, which can be C0 through C510. Once used in a user
program, counters cannot be used in any other counter instructions.
CNTD (double-word adding counter)
CDPD (double-word dual-pulse reversible counter)
CUDD (double-word up/down selection reversible counter)
For details about device ranges, see "Device Addresses" on page 2-1.
The preset value can be 0 through 4,294,967,295 and designated using a constant or a data register. If a data register is designated as the preset
value, two consecutive data registers are used.
CNTD (Double-Word Adding Counter)
For a constant, specify the value in the range of 0 to 4,294,967,295.
To indirectly specify the value, specify it with a data register number, and specify the value of the data register in the range of 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 Chapter 5 "32-bit Data Storage Setting"
in the "FC6A Series MICROSmart User's Manual".
Ladder Diagram
Reset
CNTD C0
100000
I0
Pulse
I1
I2 C0 Q0
Timing Chart
ON
Reset Input I0
OFF
ON
Pulse Input I1
OFF
ON
Counter C0
OFF
ON
Input I2
OFF
ON
Output Q0
OFF
• The preset value 0 through 4,294,967,295 can be designated
using a data register D0 through D1998; then the data of the data
registers becomes the preset value.
• Directly after the CNTD instruction, the OUT, OUTN, SET, RST,
TML, TIM, TMH, TMS, TMLO, TIMO, TMHO, or TMSO instruction
can be programmed.
Reset
I0
Pulse
I1
4-16
Counter
Program List
Instruction
LOD I0
LOD I1
CNTD C0
100000
LOD I2
AND C0
OUT Q0
99998 99999 100000
• • •
CNTD C28
D5
Q0
FC6A S MICROS
ERIES MART
Device Address
C0 to C510
C0 to C510
C0 to C510
• Double-word counter instructions use two consecutive counters,
and counters cannot be used more than once in a user program.
Data
• While the reset input is off, the counter counts the leading edges
of pulse inputs and compares them with the preset value.
• When the current value reaches the preset value, the counter
turns output on. The output stays on until the reset input is
turned on.
• When the reset input changes from off to on, the current value is
reset.
• When the reset input is on, all pulse inputs are ignored.
• The reset input must be turned off before counting may begin.
• When power is off, the counter's current value is held, and can
also be designated as "clear" type counters using Function Area
Settings (see Chapter 5 "Memory Backup" in the "FC6A Series
MICROSmart User's Manual".).
• 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 data movement when changing, confirming, and clearing
preset values, see "Changing, Confirming, and Clearing Preset
Values for Timers and Counters" on page 4-19.
• WindLDR ladder diagrams show CP (counter preset value) and
CC (counter current value) in advanced instruction devices.
• The CNTD instruction cannot be used in an interrupt program.
• If used, a user program execution error will result, turning on
special internal relay M8004 and the ERR LED on the FC6A Series
MICROSmart. For details about the user program execution
errors, see "User Program Execution Errors" on page 3-10.
L P M
ADDER ROGRAMMING ANUAL
Preset Value
Constant: 0 to 4,294,967,295
Data registers: D0 to D7999
D10000 to D61999
FC9Y-B1726