Lufft MARWIS, User Manual

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MARWIS-UMB Operating Manual V 3.3 / 9 Dec 2019
Examples:
Value Value number
(dez. / hex) 11 Bit
Identifier
(hex) IDE 18 Bit
Identifier
(hex) RTR CAN-ID
(extended)
Road temperature in °C
100d = 0x0064h
0x001 1 0x00064 0 0x00040064
Water film height in µm 600d = 0x0258h 0x001 1 0x00258 0 0x00040258
Road state 900d = 0x0384h 0x001 1 0x00384 0 0x00040384
To get the CAN-ID:
The CAN-ID is set together by 18 bit + 11 bit identifier. Example road temperature:
11 Bit 18 Bit
binär 0 0000 0000 01 00 0000 0000 0110 0100
hexadezimal 0x00 0x04 0x00 0x64
20.3.7.2 Trigger format
The first data byte of the trigger telegram indicates the trigger type. Depending on the type there
will be possible parameters that are indicated from the 2
nd data byte on.
Trigger Data
Length
Code
Data byte (hex) Parameter
1
Type
2 – 5
Parameter
Data type Description
none 1 0x00 - - -
time 5 0x01 4 Byte unsigned long Intervall in ms
difference 1 0x02 - - -
minimum 2 - 5 0x03 1 – 4 Byte Same as value Limit value
maximum 2 - 5 0x04 1 – 4 Byte Same as value Limit value
Trigger type = 0:
In case no trigger is specified the corresponding value will not be transferred.
Trigger type = 1:
The time trigger will have the value transferred in the specified interval. Take into account that
the trigger check takes place only once every 10 ms so that it makes sense to specify an interval
which is a multiple of 10 ms. Other intervals will be brought up to a round figure, e.g. a specified
interval of 111 ms will lead to a value transfer every 120 ms.
Trigger type = 2:
The trigger “difference“ will have the value transferred each time the current value differs from
the previous one. This trigger only makes sense for measuring data whose value changes
rarely, e.g. system states.
Trigger type = 3:
54 Chapter 20, Appendix