Problem writing to serial port

Hi All,
I am very new to LabVIEW (just a couple of months). I need to communicate with a serial port of an Advanced Energy RF generator (Ovation) serial port (AE Bus)
The manual talks about little endian conversion, CSR and checksum that I just can't make it work. does anybody know how to write and read to this serial port?
I have used the write and read to serial port from examples with no luck and no response from the generator. I have attached the generator's manual here, the serial commands section starts at page 65 (4-25)
Has anybody written a program to talk to Ovation RF generator? can anybody help me out and get me started? I am stuck!!!. ... appreciate your help. thanks.
~Johnny
~ Johnny
Attachments:
Ovation - AE RF generator.pdf ‏1444 KB

Thanks... so I started with the basic serial write and read, enetered hex text strings into the serial write, including the checksum and what I read back is not always correct because for example I need to calculate the XOR in the program and not just eneter it as a hex value. I should also put the write and read into a loop because I will be writing and reading to serial port 2 dozen times.
I am working with two devices, one is the generator, the other is a controller board that has a very similar serial bus structure as the generator's AE serial bus. the controller board has stepper motor drivers that move two variable capacitors. for the generator, I need to turn the power on and off and set to different power levels. for the control/stepper motor driver board: I need to read the values from a text file(attached). the text file has 3 table, table1, column1 is the number of steps that the stepper motor will move and column2 is the nominal capacitor values for C1. same thing table2; values are number of steps versus nominal cap values for C2. I need to creat a matrix such that to move the C1 to steps listed in the table, and for every step increment in C1, I need to move the C2 motor to 20 different position (listed in the table3 that has the desired percent value of total capacitance ) position and make a measurement of the impedance of the capacitors with agilant E5061 network analyzer and write the data back into the same text file at the end where it says "IMPEDANCE_REAL in Ohm one line per C1 position" and into a excel sheet too while taking a measurement... and do the same thing all over again for C2 versus C1. I think I need to use the producer consumer design pattern eventually when I get the details worked out first.
any suggestion? .... much thanks.
~ Johnny
~ Johnny
Attachments:
Basic Serial Write and Read1.vi ‏24 KB
cap-table.txt ‏7 KB

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Writing to serial port

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Attachments:
serail_comm.vi ‏52 KB

Hey Viji,
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Problem communicating via serial port in Linux

Hello,
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I get Runtime exception.
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Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException:
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at javax.comm.CommPortIdentifier.open(CommPortIdentifier.java:369)
at ParallelCommunication.initialize(ParallelCommunication.java:128)
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Thank you.

I'm having the same problem this helped somewhat debug the problem
http://bloggerdigest.blogspot.com/2006/11/linux-serial-com-port-diagnostic-test.html
I'm running Suse 10.3 and apparently it does not recognize my serial ports. So before
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Error while reading/writing to serial port

Hello,
I am trying to read/write to my serial port but
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Attachments:
error2.ppt ‏172 KB

Frederico
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1. Open the serial port at 2400 baud
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6. Power down the PT104
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Message Edited by David Crawford on 07-20-2006 10:31 AM
Attachments:
PT104 - Get Version at Power Up.vi ‏56 KB
PT104 - Get Version at Power Up.jpg ‏50 KB

Big Problems with the Serial Port

I'm Spanish and my English is not very good, I'm sorry but I need your help.
I want to connect two computers (my desktop and my handbook) with the serial port (COM2 in both sides).
I have the cable.
I have installed JBuilder 7 in both computers.
I have installed "commapi"
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I don't get in any moment receive any data.
I execute first SimpleRead and I can see what this process is waiting something. After, I execute SimpleWrite (many times), this process star and stop correctly but never the first aplication receives nothing.
I am trying for four days, I am desespereted.
I need your help is very important to me. I don't understand what is happening!!!!. This is my e-mail: [email protected]
Thank you very much.
NOTE: my handbook has just one serial port, before had a winmodem but it was eliminated.

hi,
when your notebook has only one port, how do u know that this port is COM2? I think u gave a wrong parameter for the SimpleReader or SimpleWriter so one send data to a port (say COM1) but the other receives data from another port (say COM2).
regards,
eedych

Reading and Writing For Serial Port (RS232)

Hi there;
I want to send data from my comport to a device and take data from there. I use Windows operating system. I looked at a bit javax.comm and RxTx.
Firstly do i have to use RxTx for my project because of i am using Windows operating system?And;
Where should i began to start simply send and receive data via RS232?
Edited by: furkankamaci on Feb 14, 2009 8:05 AM

Use RxTx and follow its examples.

Problems with access to serial port using reentrant code

Hi,
I have a VI that send commands and receive answers from an instrument using
de serial port.
This VI runs perfectly when used alone.
However I'm trying run two instances of that VI simultaneously using
reentrant code and I'm facing some problems.
Sometimes everything is OK but sometimes, in the process of writing to
serial port the following error happen:
Error code 36.
Invalid refnum device.
What is this?
Does someone know how to prevent this?
Thanks in advance for any help.

"Paro, Paula [CMPS:2721:EXCH]" wrote:
>
> Hi,
>
> I have a VI that send commands and receive answers from an instrument using
> de serial port.
> This VI runs perfectly when used alone.
> However I'm trying run two instances of that VI simultaneously using
> reentrant code and I'm facing some problems.
> Sometimes everything is OK but sometimes, in the process of writing to
> serial port the following error happen:
> Error code 36.
> Invalid refnum device.
>
> What is this?
> Does someone know how to prevent this?
>
> Thanks in advance for any help.
You can't use reentrant vi's vith serial vi calls without supervising of
driver.
Use VISA instead and you have to control the VISA session opening and
closing. Another word is that the only one serial port sess
ion should be
opened at a time.
Reentrant vi's for serial port without checking serial port session is a
mistake of program algorithm. Change it in any convenient way.
Sergey Krasnishov
Automated Control Systems
National Instruments Alliance Member
Moscow, Russia
[email protected]
http://acs.levsha.ru

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cu Marco

Marco,
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Best regards,
Jochen
National Instruments Germany

How to unbundling binary structure coming through the serial port

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I have a board that is transmitting a binary stream. This stream is a structure repeated constantly ... the payload of this structure looks like this
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ANALOG_COUNT is (2)
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Thanks
Alejandro
Solved!
Go to Solution.

You are still making life to difficult. Try this. It is much simpler to understand and it will work correctly. Ok, there may be some debugging.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines
Attachments:
Start.vi ‏18 KB

Problem writing to serial port

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