User Manual

Working with Projects
Tag Packages
Tags to be transferred are not all transferred at the same time, but are grouped
into packages. The number of tags in each package depends on the driver for the
controller.
To make communication as fast as possible the number of packages should be
minimized. Consecutive tags require a minimum n umber of packages, but it is
perhaps not always possible to program it this way. In such cases there is a “waste”
between two tags.
Wasteisthemaximumdistancebetweentwotagsthatcanbekeptinthesame
package. Thesizeofthewastedependsonthedriverused,andisincludedinthe
driver help file, e.g as in the table below:
Driverx Analogsignals Digitalsignals
Numberofsignals/package 2 9 124
Waste 20 0
Bit-AddressedWordsvs. RegularBitDevices
Inmostdriversitisbettertousebit-addr
essed words than regular bit devices, since
you can fit more digital devices in one tele
gram when using bit-addressed words,
than when using bit devices.
Example
Driverx Analogsignals Digitalsignals
Numberofsignals/package 2 9 124
Waste 20 0
This specific driver can have 29 analog devices or 124 digital devices in one
telegram. If you use bit-addressed words in the selected driver, you can fit 464
(29 × 16) digital devices in one package. This is almost four times as many devices.
ASCIIStrings
ASCII strings are transmitted in separate telegrams, and having a large number
of strings will affect the communication performance negatively. If an ASCII
string only has a small number of different string values, it may be a good idea to
use the Text Library function in iX Developer with predetermined contents, thus
minimizing impact on driver performance.
Relatedinformation
Text Library
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