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GF54.21-D-3003HA CAN Interface, PSM, Function




GF54.21-D-3003HA CAN Interface, PSM, Function

- with CODE (ED5) Parameterizable special module (PSM) Controller Area Network bus Class C (body manufacturer) (body manufacturer CAN)


- with CODE (ED8) Preinstallation for parameterizable special module (PSM) Controller Area Network-Bus Class C (body manufacturer) (body manufacturer CAN)

The PSM control unit has a 2nd Controller Area Network (data bus/ CAN bus) (CAN) via which, in addition to the discrete inputs and outputs, data exchange with the PSM control unit is possible. The data, which can be picked up via the Controller Area Network bus Class C (body manufacturer) (body manufacturer CAN), can be found in the "CAN matrix" in the documents "Controller Area Network matrix PSM function".

The CAN-ABH can be activated by means of a signal from the signal pool, e.g. by the signal 1018; "circuit 15 ON".

Specification:
- Highspeed CAN class C, extended CAN identifier (29 bit)
- Baud rate can be switched between 500 kbit/s, 250 kbit/s and 125 kbit/s
- Signal format = Intel (LSB first)
- Voltage (nominal) = 5 V
- Transceiver = TJA1041 (conforms to 11898)
- Terminating resistor for PSM control unit: 120 Ohms

All CAN contents can be separated and activated independently of each other by means of parameterization.

When you connect only one further body manufacturer CAN control unit (except the PSM control unit) to the body manufacturer CAN, a terminating resistor of 120 Ohms should be realized in this. If you use several control units on the body manufacturer CAN, then the last control unit should have a terminating resistor of 120 Ohms, all other control units must have a terminating resistor of approx. 3.3 k Ohms

Fleet management system (FMS)
The FMS only contains messages to be sent by the PSM control unit.
These messages contain the following information, for example:
- Vehicle speed
- Engine values
- Driver information

ISO11992-2/3
This standard contains transmit and receive messages. The transmit messages contain information similar to that for FMS, with the addition of some items of engine information. The signals received from the PSM control unit are stored in a signal pool and can be used, for example, for working speed control.

Freely assignable messages
The freely assignable messages are output as follows:
- In transmit direction: 4 messages (GPM_1H, GPM_1I, GPM_1J, GPM_1K)
- In receive direction: 4 messages (GPM_2H, GPM_2I, GPM_2J, GPM_2K)

The transmit signals are assigned from the signal pool. The receive signals are stored in the signal pool to await further use. The signals are given the designation "AuxBit, AuxByte" etc.

Details can be found in the document "Signal lists, PSM, function".

Activation of the freely assignable messages is only possible if the message package ISO11992-2/3 has also been activated. The transmit messages of the PSM control unit (GPM_1H, GPM_1I, GPM_1J and GPM_1K) will otherwise not be sent.

Structure of messages:
- 8 bit signals
- 2 byte signals
- 2 2-byte signals
- Cycle times of sent messages:
- 2 x at 100 ms
- 1 x at 500 ms
- 1 x at 1000 ms

The precise contents can be found in the "CAN matrix" in the documents "CAN matrix, PSM, function".

Parameterization for body manufacturer CAN release
The following parameters must be set when using the body manufacturer CAN:
- Body manufacturer CAN active or inactive
- "FMS standard" message package active or inactive
- "ISO11992-2/3" message package active or inactive
- Baud rate 125 kbit/s, 250 kbit/s or 500 kbit/s
- Activation of free messages