System information

General Reference Guide IO Servers Configuration

RG-001-0-EN ver 1.5 eWON® - 20/03/2009 - ©ACT'L sa Page 98

5.5.3.1 Value Name

Value name follows the syntax below:

(*) Important: See “Tags are stored as Float” on page 67

Notes:

SW type cannot be formatted as float

The eWON allows you to optimize the requests in case you need to read a lot of Tags that have been created on the UniTelWay

device. Imagine you have 100 Tags to read, the eWon will group the Tags within a predefined limit in order to make the less as

reading operations as possible. The number of Tags that can be read depends of the types of words or bits that have to be read:

SW and MW types: by groups of 50

S and M types: by groups of 200

It is possible to read one bit from a word. The syntax to add is as follows:

#0 to #31

That means that if you want to read the fourth bit from an internal data word 16 bits unsigned that you address MW0, you have to add

"#4" at the end of the address: MW0#4.

The type of words for which this syntax can be applied are:

MWxW, MWxI, MWxD, MWxL, SWxW, SWxI, SWxD and SWxL (please report to the table above).

• Status register:

The STATUS Tag is a special Tag that returns information about the current state of the communication for a given device. As for other Tags, the

status Tag ValueName is composed of:

Status, Global Device Address

• You can define a status Tag for each PLC used.

• If you use the status address, the Tag must be configured as analog.

MWxW Internal data word 16 bits (unsigned)

MWxI Internal data word 16 bits (signed)

MWxD Internal data word 32 bits as DWORD (unsigned) (*)

MWxF Internal data word 32 bits as IEEE float

MWxL Internal data word 32 bits as LONG (signed) (*)

SWxW System data word 16 bits (unsigned)

SWxI System data word 16 bits (signed)

SWxD System data word 32 bits as DWORD (unsigned) (*)

SWxL System data word 32 bits as LONG (signed) (*)

Mx Internal data bit

Sx System data bit

Table 71: value names for UNITE addresses

Communication not initialized. Status UNKNOWN.

If no Tag is polled on that device address, the communication status is unknown.

1 Communication OK.

2 Communication NOT OK.

Table 72: Tag Status meaning