Multi-Tech Systems 7500 Manuale Utente

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ION 7500 / ION 7600 User’s Guide
Basics of ION Architecture
Chapter 4 - Using ION Software 
Page 105
Sequence of ION Module Execution
ION modules always execute in the order of the data flow (in the example below, 
from 1 to 4). This logical execution order is maintained even if you created the 
framework from back to front.
ION modules may execute simultaneously if they do not depend on each other for 
data (such as both ION modules labelled 1). Conversely, ION module 3 will not 
execute until both ION modules 1 and ION module 2 have executed.
ION Registers
Each module has one or more output registers, and most modules have Setup 
registers. (A module’s inputs are links to the output registers on other modules.) 
There are different types of registers, each classified by the type of data they accept. 
When you want to change a module’s configuration, you must supply the type of 
data that is appropriate for the register you are configuring. The configuration 
tools prevent you from entering the wrong type of data into a register, but they do 
not prevent you from entering the wrong value.
The ‘N
OT
 A
VAILABLE
’ Value
An ION module that requires a link to one or more of its inputs, but has no such 
links created, does not contain any values in its output registers. Instead, its output 
registers are set to N
OT
 A
VAILABLE
. In addition, if a module has an input that is 
invalid (for example, a line-to-neutral measurement for a 3-wire Delta system) its 
output register is also set to N
OT
 A
VAILABLE
. The N
OT
 A
VAILABLE
 value helps to 
distinguish between cases where a register contains a value like 0 or 
OFF
, and cases 
where there is actually no value stored.
N
OTE
The N
OT
 A
VAILABLE
 value appears in Vista objects that are linked to ION modules with output registers
that are N
OT
 A
VAILABLE
. The front panel of the meter displays values that are N
OT
 A
VAILABLE
 as dashes (–).
If the inputs of a module are N
OT
 A
VAILABLE
, its output registers are also N
OT
 
A
VAILABLE
. The N
OT
 A
VAILABLE
 value propagates through all linked modules. 
(The N
OT
 A
VAILABLE
 value propagates through linked Arithmetic modules 
differently - refer to the ION Arithmetic module description in the online
ION Programmer’s Reference.)
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1
2
3
4