PSM Signal Concept, Basic Function - GF54.21-S-1004A

Model All (Light transporter) 

Overview 

This document contains information on:

• General 
• Function 
  • Signal pool input 
  • Signal pool output 
  • Status indication 
  • Special signals 

General 

The signal pool contains signals for free use by the customer and for internal functions. The signal sources are:

• Values of internal functions
• Constants (e.g. for bits, bytes)
• Signals of CAN interfaces
• Status of inputs and outputs
• Results of programmable logic controller (PLC) function blocks: Logics, arithmetic unit

Function 

The signals are available as a bit, byte, data word ("Word") (2 bytes), double word ("DWord") (4 bytes), signed double word ("signed DWord") (2 bytes) and signed double word ("signed DWord") (4 bytes). Every signal has a unique 2 byte identification number of the signal (signal ID).

Each signal has one source only. A signal can be used in none of the outputs, one of the outputs or in several outputs as well as internally. Each signal, before it is written into the signal pool, is checked by the source for plausibility and validity. The signal pool is specific to the model series.

Signal pool input 

Each signal has just one source.

Signal pool output 

Each signal can be assigned through coding to one or more outputs as well as be used internally. Individual signals can be dependent on other signals, e.g. terminal 15.

Status indication 

The value of each signal can be represented in XENTRY Diagnosis COM Kit using the menu item "Display signal values". The menu item is available in the "Actual values" tab and in the expert coding.

Special signals 

The following special signals exist:

• "Permanent LOW" signal, gives a logical "0" at the input at which the signal is applied.
• "Permanent HIGH" signal, gives a logical "1" at the input at which the signal is applied.
• The "Prompt deactivated", deactivates the prompt for this input.