Using CitectSCADA > Communicating with I/O Devices > Using a Disk I/O Device > Disk I/O device setup

Disk I/O Device setup

To set up communications with a device, follow the basic steps given in the I/O Device setup procedure below.

Sometimes you might need to edit the communications forms directly. They require the following specific information.

Perform the setup by entering the following information:

Text Box Required information

I/O Device name

A name or your Disk I/O Device, for example: DISK_PLC. Each I/O Device needs to have a unique name in the CitectSCADA system.

I/O Device number

A unique number for the disk I/O Device (1-4095). Each I/O Device needs to have a unique number in the CitectSCADA system.

I/O Device address

The path and filename of the disk file, for example:

[RUN]:DSKDRV.DSK

If you are using redundant disk I/O Devices, specify the path to both the primary file and the Standby file in the configuration of both disk I/O Devices.

For example, if this is the primary disk I/O Device, enter:

Primary_File, Standby_File

If this is the Standby Disk I/O Device enter:

Standby_File, Primary File

Primary_File is the name (and path) of the primary disk I/O Device file. You may use path substitution in this part of the field.

Standby_File is the name (and path) of the Standby Disk I/O Device file. You may use path substitution in this part of the field.

Notes:

  • If the specified disk I/O device file is not found, CitectSCADA creates a new (empty) file with the specified filename.
  • To use redundant disk I/O devices, you need to use a network that supports peer-to-peer communication.
  • Disk files need to have write permission (on both primary and standby servers).
  • The frequency with which CitectSCADA writes data to the disk I/O device(s) is determined by the [DiskDrv]UpDateTime parameter.

I/O Device protocol

To use the CitectSCADAgeneric protocol, enter: GENERIC

- or -

To select a specific protocol supported by CitectSCADA, see the I/O Devices online Help.

I/O Device port name

You need to use: DISKDRV

I/O Device comment

Any useful comment.

I/O Device startup mode

If not using redundant disk I/O Devices, leave this property blank.

If you are using redundant disk I/O Devices, use either:

Primary: Enable immediate use of this disk I/O Device

StandbyWrite: This disk I/O Device will remain unused until the computer with the primary disk I/O device configured becomes inoperative. Every write request sent to the primary disk I/O Device is also sent to this disk I/O Device.

To use StandbyWrite mode, you need to also configure an I/O disk device in the primary server. Both I/O Devices need to have the same I/O Device name and number.

I/O Device Log Write, Log Read, Cache and Cache Time

Leave these properties blank.

See Also

Redundant Disk I/O Devices
Disk I/O Device Errors