LIN Bus 13 Bit Synch Break

[jinyih]

I am attempting to use LabVIEW to create a 13 Bit Synch Break for the LIN Bus.My current method is by initializing the serial port to a baud rate of 6500 and then by using the Serial Port Break vi with a 2 ms delay to achieve the 13 Bit Synch Break. I would have to reinitialize the serial port baud rate to 9600 after the Serial Port Break vi so that i can communicate with the unit that I am working with.Is there any other way that I can do that with LabVIEW?Thank you. 

[Chris_R.]

Hello,

Unfortunately, we do not have products or support for LIN Bus, but I can try to help you with your serial communications.  I do not know what the Synch Break is for LIN Bus or how it works, but is it exactly a 13 bit break that you need?  You can manipulate the number of bits of transmission by changing the number of data bits and stop bits when configuring the port.  With the Serial Port Break, the data transmission will pause until the break is unasserted.  If you want an empty 13 bit frame in the transmission, you will need to use other properties to do that.  (Break Len and ASRL End Out).  By setting the number of bits accordingly and using these properties, you should be able to get an appropriately sized break without having to set a certain wait time.  What version of LabVIEW are you using?  The Serial Port Break.vi is older and has been replaced by the VISA Serial Break.vi that uses these properties.  With any wait, especially with the low number of milliseconds you are using, it may not be very accurate.  If you set a wait of 2 ms in your program, it will wait a minimum of 2 ms, so other factors may cause the actual wait to increase.  Let me know if this helps.  Have a great day!

Chris R.

Applications Engineer

National Instruments

[jinyih]

Thank you for your help!The Synch Break that i require must be 13 Bits or more,dont hv to be exactly 13 Bits.I am using LabVIEW 6.1 at the moment.I looked at the VISA Serial Break VI but didnt see the properties that u told me about. 

[Chris_R.]

Hello,
Those properties are available in LabVIEW 6.1, but they have slightly different names in the property lists.  They can be found in the property listing of the VISA property node by going to Serial Settings>>Break Length and Serial Settings>>Serial End Mode for Writes.  I have attached the version I am looking at below.  See if it will work for you and let me know.  Have a great day!

Chris R.

[jinyih]

I have managed to achieve the 13-Bits Synch Break alry!Thank you!Have a nice day!

[Chris_R.]

That's great!  If possible, please post how you were able to get it to work.  Thanks and have a great day!

Chris R.

[Majicz]

please tell me how you manage to get the 13-Bits Synch Break