Checking The File Password Registration Status - Mitsubishi Electric M800VW Series Manual

M800V/M80V Series PLC Development Manual
5 Peripheral Development Environment (GX Works2)
5.12 File Password Function

5.12.5 Checking the File Password Registration Status

You can check that a password is registered to a file in the CNC by using the values of special registers SD553 to SD556.
Monitoring the values of the special registers prevents you from forgetting to resister the password.
The password registration can be checked by a project basis. Bit0 to bit5 of each special register correspond to the project
Nos. 1 to 6. The corresponding bit value of each project changes depending on the status of the password registration.
bitF bit8 bit7
SD553
to
SD556
The values of the special registers change depending on the status of the password registration for stored file. However, the
target file of the register and condition to change the value differ for the respective registers. For details, refer to the following
table.
Special register
SD553 Sequence programs
SD554 Sequence programs
SD555 PLC message, device comment
SD556 PLC message, device comment
Note that when no target file is stored in the project, the bit which corresponds to the project is "0".
Including each special register in a sequence program enables the CNC to stop the operation or to display an alarm, when a
password has not been registered.
In the example below, PLC message is displayed when no password is registered for the ladder file of project 1. This prevents
you from forgetting to register the password. (Refer to "5.8 PLC Message Development")
Example of a sequence program
Example of a PLC message
A,0,10, Password is not registered.
bit6 bit5 bit4 bit3 bit2
Target file Bit value and its condition corresponding to project No.
0 (When at least one password is registered)
1 (Other cases)
0 (When all files are protected by passwords)
1 (Other cases)
0 (When at least one password is registered)
1 (Other cases)
0 (When all files are protected by passwords)
1 (Other cases)
When the value of SD553 is
not "0", "F0" is turned ON.
When "F0" is turned ON, an
PLC message is displayed.
bit1 bit0
Status of the password registration for each
project
Project No.1
Project No.2
Project No.3
Project No.4
Project No.5
Project No.6
Status of the password
registration of safety PLC 1
Status of the password
registration of safety PLC 2
Not used
213 IB-1501614-B