Signal Concept, PSM, Function - GF54.21-S-2000TRA
Model 447
with code ED5 (Parameterisable special module)
except code XM7 (MOPF II)
Model 448
with code ED5 (Parameterisable special module)
except code XM7 (MOPF II)
Signal flow in parameterizable special module (PSM) control unit (N26/16)
Function overview and brief description of signal pool
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)
- Interfaces of vehicle interior CAN (CAN B) and peripheral devices CAN
- Signals from vehicle interior CAN (CAN B) interfaces
- Status of multifunction inputs and multifunction outputs
- Results of programmable logic controller (PLC) function blocks: Logics, arithmetic unit
The signals are available as a bit word, byte word, 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) signals. 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 may be dependent on other signals, e.g. terminal 15.
Signal types
The following signal types exist:
- Bit information (e.g. terminal 15)
- 1-byte information (e.g. terminal 85), (0 to 255)
- 2-byte information (e.g. central locking system), (0 to 65 535)
- Multi-byte information as pointer (e.g. vehicle identification number (VIN))
Status display
The value of each signal from the signal pool can be read out using the diagnosis service "Read PLC signal pool". This diagnosis service is only available in the "Extended Session".
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
- "Prompt deactivated" signal, deactivates the prompt for this input
| Parameterizable special module (PSM) control unit component description | GF54.21-S-5005TRA | ||
| Overview of system components for parameterizable special module (PSM) | GF54.21-S-9998TRA |