Hi everyone,
I'm new to Labview and LIN-Bus and seem to encounter the same problem as mad_madridista.
I read the LIN-Spec, the Hardware Manual and a lot of threads but it's getting more and more confusing. So I thought this could become a kind of "First-Steps-with-8476-Module-for-LIN-and-LV-Newbies-Thread"?
The situation is as follows:
I want to use a 8476-module and Labview 2013 to communicate with a product
The module is connected (via USB) and recognized by MAX. I assigned Port: LIN0 and Baudrate: 19200 (as specified for the product).
The connector of product has the following pins:
- 12 V plus potential
- 12 V ground
- LIN
- Interlock in
- Interlock out
I connected the 12V+ to VBat; the 12V- to both ground Pins and LIN to LIN. Also I connected a 12V-power supply (5A max) to the 12V+ and 12V-. So the first question is: is this it? Here it seems like some resistors and diodes need to be added; but as I read it from the NI-CAN Hardware and Software Manual, 4-26, this isn't needed on NI USB-Lin products.
I'm assuming that everything is correct by the means of hardware and will proceed.
I want the 8476 (or more specifically the .vi) to be the master, because I want to control the product. My understanding is, that this is possible with the example .vi's (e.g. LIN Master Send Full Frame and Receive.vi), by simply sending an ID (or more correctly: a Frame Header) to the BUS and having my product react to it. Is it that simple?
I had an ldf coming with the product, where the frames and signals are described:
LIN_description_file;
LIN_protocol_version = "2.0";
LIN_language_version = "2.0";
LIN_speed = 19.2 kbps;
Nodes {
Master: PC, 5 ms, 0.2 ms;
Slaves: ..., HEIZER;
}
Signals {
...
Geraet_ein: 1, 0, PC, GERAET;
...
Temp_Sensor: 8, 254, GERAET, PC;
...
}
Diagnostic_signals {
...
}
Frames {
...
Ger_01: 28, PC, 4 {
...
Geraet_ein, 8;
Ger_02: 48, GERAET, 8 {
...
Temp_Sensor, 48;
...
}
...
}
}
Diagnostic_frames {
...
Node_attributes {
...
GERAET {
LIN_protocol = 2.0;
configured_NAD=0x5F;
product_id=0x0006, 0x0000, 0x00;
response_error =Geraet_ResponseError;
P2_min = 10 ms;
ST_min = 10 ms;
configurable_frames {
Ger_01 = 0x401C;
Ger_02 = 0x4030;
}
}
}
Schedule_tables {
main {
Ger_01 delay 10 ms;
...
Ger_02 delay 10 ms;
...
}
}
Signal_encoding_types {
...
Temp_Sensor_encoding {
logical_value, 254, "Init";
logical_value, 255, "Fehler";
physical_value, 0, 220, 1, -50, "Unit_DegreCelsi";
}
...
HZ_Off_On {
logical_value, 0, "Aus";
logical_value, 1, "Ein";
}
}
Signal_representation {
...
Temp_Sensor_encoding: Temp_Sensor
...
HZ_Off_On: Geraet_ein
...
}
In order to read "Temp_Sensor" my assumption was that I need to send the Header-ID "48" to the BUS because of
Frames {
Ger_02: 48, GERAET, 8 {
With "LIN Master Send Header Frame an Receive.vi" it seems possible to "Write Header Frame", but the problem starts with the fact, that It won't accept the "ArbitrationId: 48". Then I thought this might be hexadecimal, and with "ArbitrationId: 30" there is something happening (see screenshot), but I'm still getting no response from the slave.
So, I hope somebody could tell me where I am going wrong!
Thanks!
