Mitsubishi Digital Electronics FX2NC Manual

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FX Series Programmable Controlers Applied Instructions 5

5-61

5.6.8 PLSY (FNC 57)

Operation:

A specified quantit

y

of pulses S

2

is output throu

g

h

device D at a specified frequenc

y

S

1

. This

instruction is used in situations where the quantit

y

of outputs is of primar

y

concern.

Points to note:

a) Users of the FX PLC can specif

y

output

frequencies (S

1

) of 1 to 1000Hz. Users of FX

Version 2.2 or earlier will need to initialize the

PLSY instruction. The pro

g

ram to the ri

g

ht can be

used to achieve this. FX

0

/FX

0N

users ma

y

use

frequencies of 10to 2000Hz. FX

2N

users ma

y

use

frequencies of 2 to 20000Hz.

b) The maximum number of pulses: 16 bit operation:

1 to 32,767 pulses, 32 bit operation: 1 to 2,147,483,647 pulses.

Note: special auxiliar

y

coil M8029 is turned ON when the specified number of pulses has

been completed. The pulse count and completion fla

g

(M8029) are reset when the PLSY

instruction is de-ener

g

ized. If “0" (zero) is specified the PLSY instruction will continue

g

eneratin

g

pulses for as lon

g

as the instruction is ener

g

ized.

c) A sin

g

le pulse is described as havin

g

a 50% dut

y

c

y

cle. This means it is ON for 50% of the

pulse and consequentl

y

OFF for the remainin

g

50% of the pulse. The actual output is

controlled b

y

interrupt handlin

g

, i.e. the output c

y

cle is NOT affected b

y

the scan time of the

pro

g

ram.

d) The data in operands S

1

and S

2

ma

y

be chan

g

ed durin

g

execution. However, the new data

in S

2

will not become effective until the current operation has been completed, i.e. the

instruction has been reset b

y

removal of the drive contact.

e) This instruction can onl

y

be used once within a pro

g

ram scan. Also, onl

y

one of either FNC

57 PLSY or FNC 59 PLSR can be in the active pro

g

ram at once.

f) Because of the nature of the hi

g

h speed output, transistor output units should be used with

this instruction. Rela

y

outputs will suffer from a

g

reatl

y

reduced life and will cause false

outputs to occur due to the mechanical ‘bounce’ of the contacts.

To ensure a ‘clean’ output si

g

nal when usin

g

transistor units, the load current should be

200mA or hi

g

her. It ma

y

be found that ‘pull up’ resistors will be required.

Mnemonic Function

Operands

Program steps

S

1

S

2

D

PLSY

FNC 57

(Pulse Y

output)

Outputs a

specified number

of pulses at a set

frequenc

y

K, H,

KnX, KnY,

KnM, KnS,

T, C, D, V, Z

Y

Note:

FX

0(S)

/FX

0N

users:

Y000 onl

y



.

FX users:

an

y

Y

PPP

.

FX

2N(C)

users: Y000 or

Y001 onl

y



.

PLSY:

7 steps

DPLSY:

13steps

X10

D 0K1000 Y 0PLSY

[ S1 ]

[ S2 ]

[ D ]

S2 D

PLSY

M8002

M8034

M8002

S1

It is possible to use subroutines or other such pro

g

rammin

g

techniques to isolate different

instances of this instructions. In this case, the current instruction must be deactivated before

chan

g

in

g

to the new instance.