FX Series Programmable Controllers

Devices in Detail 4

4.5Pointers

FX1S

FX1N

FX2N

FX2NC

Device Mnemonic: P

Purpose: Program flow control

Alias: Pointer

Program pointer

P

Available forms: Label: appears on the left of the left hand bus bar when the program is viewed in ladder mode.

Devices numbered in: Decimal, i.e. P0 to P9, P10 to P19

Further uses: Can be used with conditional jump statements (CJ function 00)

-see page 5-5 and item on the example device usage diagram. Can be used with call statements

-see page 5-7 and item on the example device usage diagram

Example device usage:

X20

 

CJ

P0

1

 

P0

 

X20

CALL P1

2

FEND

P1

SRET

Available devices:

FX1S PLC’s have 64 pointers; available from the range of P0 to P63.

FX1N, FX2N and FX2NC PLC’s have 128 pointers; available from the range of P0 to P127.

Jumping to the end of the program:

When using conditional jump instructions (CJ, function 00) the program end can be jumped to automatically by using the pointer P63 within the CJ instruction. Labelling the END instruction with P63 is not required.

Device availability:

• For more information about device availability for individual PLC’s, please see chapter 8.

4-10

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Mitsubishi Electronics FX1S manual Pointers, Jumping to the end of the program, Device availability, Device Mnemonic P