7 MEMORY CONFIGURATION AND DATA PROCESS

MELSEC-Q

(1)Transmitting data when power is turned ON or PLC CPU is reset

( )

When the power is turned ON or the PLC CPU is reset, the "parameters", "positioning data" and "block start data" stored (backed up) in the flash ROM is transmitted to the buffer memory.

(2) Transmitting data with TO command from PLC CPU ( )

The parameters or data is written from the PLC CPU to the buffer memory using the TO command. At this time, when the "parameter area (b) 1", "positioning data (No. 1 to 600)", "block start data (No. 7000 to 7004)", "control data" and "PLC CPU memo area" are written into the buffer memory with the TO command, it is simultaneously valid.

1 Parameter area (b)

Parameters validated simultaneously with the writing

 

to the buffer memory with the TO command.

 

(

 

to

 

,

 

to

 

)

 

Pr.8

Pr.10

Pr.25

Pr.42

(3)Validate parameters when PLC READY signal [Y0] changes from OFF to ON

When the PLC READY signal [Y0] changes from OFF to ON, the data stored in the buffer memory's "parameter area (a) 2" is validated.

For Pr.5 , however, only the data obtained first after the PLC READY signal [Y0]

changes from OFF to ON when the power is turned ON or PLC CPU is reset becomes validate.

(Refer to Section 5.2 "List of parameters" for details.)

2: Parameter area (a) .... Parameters validated when PLC READY signal [Y0]

changes from OFF to ON.

(

 

Pr.1

to

 

Pr.7

,

Pr.11

to

Pr.24

,

Pr.43

 

 

 

 

 

to

 

Pr.57

, Pr.150 )

POINT

The setting values of the parameters that correspond to parameter area (b) are valid when written into the buffer memory with the TO command.

However, the setting values of the parameters that correspond to parameter area

(a)are not validated until the PLC READY signal [Y0] changes from OFF to ON.

(4)Accessing with FROM command from PLC CPU ( )

The data is read from the buffer memory to the PLC CPU using the FROM command.

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Mitsubishi Electronics QD75D Transmitting data with to command from PLC CPU, Accessing with from command from PLC CPU