Serial port settings

I can not communicate with a serial device using the Labview 6 example program. I suspect that the baud rate or stop bit setting is wrong. How do I change it?
We have Labview version 6.
Attachments:
SerialComm1.vi ‏45 KB

Hi RayPh,
Are you able to communicate with the instrument using other application software such as HyperTerminal?
If so, check the settings under properties.
In Labview: At the Block Diagram, select Instrument IO from the Functions Palette. Select Serial and choose "VISA Configure Serial Port". Wire the configuration settings from the application software to this vi.
The Context Help will show a description of each terminal and their default settings.
You can also check the following link for more details:
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=137&HOID=5065000000050000008E490100&HTHREAD=000084366&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0

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Instrument I/O Assistant refuses to save serial port settings

(I'm using Labview 7.1 on
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I have successfully communicated with the device on this computer using
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I have successfully communicated with the device through Labview on another
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I am using the Instrument I/O assistant to get things up and running, this
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When I click on COM1port "properties" in the "select
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Serial port reads unconventional characters

Hi,
     I'm using the serial port to read 32 8bit numbers and have been getting some strange characters read back.
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hi there
i bet there's something wrong with the serial port settings
- Enable Termination Char (T)
- Termination Char
- data rate
- data bits
- polarity
- stop bits
you can adjust these settings with the "VISA Configure Serial Port.vi". please check if the settings are correct.
you wrote "However if I use AComPort to read one byte at a time (rather than a string) I get the correct numbers", so try 8 databits, 1 stopbit, no parity and disabled termination character or see the documentation of AComPort .
Best regards
chris
CL(A)Dly bending G-Force with LabVIEW
famous last words: "oh my god, it is full of stars!"

VISA Configure Serial Port setzt RxD auf +5.8V

Hallo,
Ich habe ein Problem mit dem Empfangen von Daten von einem Mikrocontroller.
Das Testprogramm auf dem Microcontroller (TC1796) sendet beim Empfang des ASCII-Zeichens “J“ (0x4A) das ASCII-Zeichen “_“ (0x5F) zurück. Als Pegelwandler wird ein MAX232 verwendet.
Wenn ich "J" mit einem Hyperterminal sende, kommt das Zeichen wie gewünscht zurück.
Wenn ich jedoch das Selbe mit LabView mache, empfängt der Mikrocontroller das "J", sendet "_" zurück, was aber von Labview nicht empfangen wird.
Dabei habe ich das Beispielprogramm von LabView verwendet.
Zum Testen habe ich einfach mal probiert, die beiden Pins RxD und TxD der seriellen Schnittstelle des PCs kurzzuschließen (Loopback).
Die von LabView gesendeten Zeichen wurden empfangen.
Als nächstens habe ich die Signale am Oszilloskop gemessen. Dabei ist mir aufgefallen, dass LabView beim Herstellen der Verbindung zum Port, die RxD-Leitung dauerhaft auf +5.8V setzt (auch wenn der Mikrocontroller gar nicht verbunden ist)
Das Hyperterminal macht das im Gegensatz dazu aber nicht...
An was kann das liegen?
Im Anhang sind die Bilder vom Oszillosop
Attachments:
RS232_LabView.png ‏23 KB
RS232_Terminal.png ‏23 KB
Connect_to_Port_LabView.png ‏16 KB

Hallo student,
1. Dies ist ein englischsprachiges Forum, wenn du viele Antworten haben willst, solltest du also in englisch posten. Alternativ gibt es auch ein deutschsprachiges Forum: www.labviewforum.de !
2. Statt der Oszilloskopbilder wäre es hilfreicher, wenn du dein VI angehängt hättest - oder wenigstens Bilder von dessen Blockdiagramm.
3. Hilfreich bei solchen Sachen ist es auch, die Kommunikationsparameter zu überprüfen (von Baudrate bis TermChar)!
Nachtrag zu 1.: Crossposts bitte in beiden Foren entsprechend mit Links kennzeichnen!
For the English speaking reader:
I told him to post in English, to attach VI (or block diagram picture) instead of scope plots, and to check serial port settings including termchar.
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

Missing Bluetooth Settings - Serial Ports

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Can we have them back??

Hi,
I am having the same problem, could you find a solution?
Do you know if there is way to do the same thing from terminal?
Since I am pretty new to this advanced configuration, do you think this software could be useful for our case:
http://freeware.the-meiers.org
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Unwanted data strings in settings, for connectivity to serial port.

When my program connects to the unit, threw the serial port its recording an unwanted string value in my setting files. Causing "19,Read Key (Boolean).vie" Error to be recorded. Unable to locate where and why this is happening in my VI. Im very new to labview and still learning the basic. I have came up with the conclusion that this error started to happen ever since the last LABVIEW update. (Version 13.0f2).
Thank you,

This is my original copy of my labview code, i thought maybe updating it was causing the error 19.
The first Settings.ini is before my code is ran, second is the error after the code is ran.
I inherited a program and im trying to follow all the code to key in where the code is causing the error. Im not sure what exactly code I should post.
Attachments:
Settings.ini ‏1 KB
Settings.ini ‏1 KB

How to get data from serial port to GUI textArea

From Serial Port.....
Messages from base (always 5 bytes):
0xAA, 0, 0, 0, 0xBB - IDLE Mode
0xAA, 0, 0x80, 0x80, 0xBB - Question Mode
messages from terminal (always 6 bytes):
0xAA, a, b, c, chksum, 0xBB
where chksum = a+b+c;
a = address (0-250)
the 2 MSB's of b represenet the answer:
0 0 - A
0 1 - B
1 0 - C
1 1 - D
the 6LSB's of b and 8bits of c is the time for answer, in milliseconds.
(0-16384 milliseconds)
I have VB Code for that but I want the same thing in Java ...
Can any one help me?
Here's VB Code..
VERSION 5.00
Object = "{648A5603-2C6E-101B-82B6-000000000014}#1.1#0"; "MSCOMM32.OCX"
Begin VB.Form Form1
   BorderStyle     =   1 'Fixed Single
   Caption         =   "Aakar GUI"
   ClientHeight    =   4665
   ClientLeft      =   60
   ClientTop       =   375
   ClientWidth     =   6105
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   311
   ScaleMode       =   3 'Pixel
   ScaleWidth      =   407
   StartUpPosition =   3 'Windows Default
   Begin VB.CommandButton cmdPort
      Caption         =   "Open Port"
      Height          =   375
      Left            =   120
      TabIndex        =   4
      Top             =   600
      Width           =   1455
   End
   Begin VB.ComboBox cmbPort
      Height          =   315
      ItemData        =   "Form1.frx":0000
      Left            =   120
      List            =   "Form1.frx":0016
      Style           =   2 'Dropdown List
      TabIndex        =   3
      Top             =   120
      Width           =   2895
   End
   Begin VB.CommandButton cmdEnd
      Caption         =   "End"
      Height          =   495
      Left            =   1560
      TabIndex        =   2
      Top             =   1320
      Width           =   1215
   End
   Begin VB.CommandButton cmdStart
      Caption         =   "Start"
      Height          =   495
      Left            =   120
      TabIndex        =   1
      Top             =   1320
      Width           =   1215
   End
   Begin VB.TextBox txtMessage
      Height          =   2040
      Left            =   119
      MultiLine       =   -1 'True
      ScrollBars      =   3 'Both
      TabIndex        =   0
      Top             =   2475
      Width           =   5848
   End
   Begin VB.Timer tmrRead
      Enabled         =   0   'False
      Interval        =   1
      Left            =   2040
      Top             =   600
   End
   Begin MSCommLib.MSComm MSComm1
      Left            =   3120
      Top             =   360
      _ExtentX        =   1164
      _ExtentY        =   1164
      _Version        =   393216
      DTREnable       =   0   'False
      ParityReplace   =   45
      SThreshold      =   1
   End
   Begin VB.Label Label5
      Caption         =   "Result Data:"
      Height          =   375
      Left            =   120
      TabIndex        =   5
      Top             =   2115
      Width           =   1320
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Dim PortIsOpen As Boolean
Dim Answers(4) As String
Dim RejectKeystroke As Boolean
Private Sub cmbPort_Change()
Debug.Print cmbPort.ListIndex
End Sub
Private Sub cmbPort_Validate(Cancel As Boolean)
'Cancel = True
End Sub
Private Sub cmdEnd_Click()
MSComm1.Output = "e"
txtMessage.Text = ""
End Sub
Private Sub cmdPort_Click()
On Error GoTo ErrorHandler
If cmbPort.ListIndex < 0 Then Exit Sub
If PortIsOpen Then
    cmbPort.Enabled = True
    MSComm1.PortOpen = False
    PortIsOpen = False
    cmdPort.Caption = "Open Port"
    cmdStart.Enabled = False
    cmdEnd.Enabled = False
Else
    MSComm1.CommPort = cmbPort.ListIndex + 1
    cmbPort.Enabled = False
    MSComm1.PortOpen = True
    PortIsOpen = True
    cmdPort.Caption = "Close Port"
    cmdStart.Enabled = True
    cmdEnd.Enabled = True
End If
Exit Sub
ErrorHandler:
Debug.Print Err.Number
Debug.Print Err.Description
MsgBox Err.Description, vbExclamation Or vbOKOnly, "Error opening port"
cmbPort.Enabled = True
PortIsOpen = False
cmdPort.Caption = "Open Port"
cmdStart.Enabled = False
cmdEnd.Enabled = False
End Sub
Private Sub cmdStart_Click()
MSComm1.Output = "s"
txtMessage.Text = ""
End Sub
Private Sub Form_Initialize()
Dim tmp As Variant
tmp = InitCommonControls
End Sub
Private Sub Form_Load()
Answers(0) = "A"
Answers(1) = "B"
Answers(2) = "C"
Answers(3) = "D"
'MSComm1.Settings = "9600,n,8,1"
''MSComm1.Settings = "115200,n,8,1"
'MSComm1.PortOpen = True
On Error GoTo ErrorHandler1
MSComm1.CommPort = 1                    ' comm port 1
MSComm1.RThreshold = 1                  ' use 'on comm' event processing
MSComm1.Settings = "9600,n,8,1"         ' baud, parity, data bits, stop bits
MSComm1.SThreshold = 1                  ' allows us to track Tx LED
MSComm1.InputMode = comInputModeText    'comInputModeBinary ' binary mode, you can also use
                                        ' comInputModeText for text only use
PortIsOpen = False
cmbPort.ListIndex = 0
' open the port
MSComm1.PortOpen = True
cmbPort.Enabled = False
PortIsOpen = True
cmdPort.Caption = "Close Port"
cmdStart.Enabled = True
cmdEnd.Enabled = True
Exit Sub
ErrorHandler1:
Debug.Print Err.Description
PortIsOpen = False
cmbPort.Enabled = True
cmdPort.Caption = "Open Port"
cmdStart.Enabled = False
cmdEnd.Enabled = False
End Sub
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
If MSComm1.PortOpen Then MSComm1.PortOpen = False
End Sub
Private Sub lblOption_Click()
End Sub
Private Sub MSComm1_OnComm()
' Synopsis:     Handle incoming characters, 'On Comm' Event
' Description: By setting MSComm1.RThreshold = 1, this event will fire for
'               each character that arrives in the comm controls input buffer.
'               Set MSComm1.RThreshold = 0 if you want to poll the control
'               yourself, either via a TImer or within program execution loop.
'               In most cases, OnComm Event processing shown here is the prefered
'               method of processing incoming characters.
    Dim i As Long
    Dim sBuff    As String           ' buffer for holding incoming characters
    Const MTC       As String = vbCrLf ' message terminator characters (ususally vbCrLf)
    Const LenMTC    As Long = 2         ' number of terminator characters, must match MTC
    Dim iPtr        As Long             ' pointer to terminatior character
    ' OnComm fires for multiple Events
    ' so get the Event ID & process
    Select Case MSComm1.CommEvent
        ' Received RThreshold # of chars, in our case 1.
        Case comEvReceive
            ' read all of the characters from the input buffer
            ' StrConv() is required when using MSComm in binary mode,
            ' if you set MSComm1.InputMode = comInputModeText, it's not required
            'sBuff = sBuff & StrConv(MSComm1.Input, vbUnicode)
            'If Len(txtMessage.Text) > 4096 Then txtMessage.Text = ""
            sBuff = MSComm1.Input
            Dim ch As String
            Dim PacketStart As Boolean
            Dim PacketLength As Integer
            Dim Packet() As String
            PacketStart = False
            PacketLength = 0
            While (Len(sBuff) > 0)
                ch = Left(sBuff, 1)
                If (ch = Chr(&HAA)) Then PacketStart = True
                If (ch = Chr(&HBB)) Then PacketStart = False
                If (ch <> Chr(&HAA) And ch <> Chr(&HBB)) Then
                    PacketLength = PacketLength + 1
                    ReDim Preserve Packet(PacketLength)
                    Packet(PacketLength) = ch
                End If
                'txtMessage.Text = txtMessage.Text + Format(Hex(Asc(ch)), " @@")
                sBuff = Right(sBuff, Len(sBuff) - 1)
            Wend
            If (PacketLength = 3) Then
                Debug.Print "Command packet recieved"
                'txtMessage.Text = txtMessage.Text + vbCrLf + "Address =" + Str(Asc(Packet(1)))
                'txtMessage.Text = txtMessage.Text + vbCrLf + "Address =" + Str(Asc(Packet(2)))
            End If
            If (PacketLength = 4) Then
                Debug.Print "Response packet recieved"
                txtMessage.Text = txtMessage.Text + "Address =" + Str(Asc(Packet(1))) + _
                    " Answer = " + Answers((Asc(Packet(2)) And &HC0) / 64) + _
                    " Time =" + Str((Asc(Packet(2)) And &H3F) * 256 + (Asc(Packet(3)))) + "mS" + vbCrLf
                'txtMessage.Text = txtMessage.Text + vbCrLf + "Address =" + Str(Asc(Packet(1)))
                'txtMessage.Text = txtMessage.Text + vbCrLf + "Option =" + Str((Asc(Packet(2)) And &HC0) / 64)
                'txtMessage.Text = txtMessage.Text + vbCrLf + "Time =" + Str((Asc(Packet(2)) And &H3F) * 256 + (Asc(Packet(3))))
            End If
            If (PacketLength <> 4 And PacketLength <> 3) Then Debug.Print "Unknown packet of length" + Str(PacketLength) + " recieved"
            txtMessage.Text = txtMessage.Text + vbCrLf
        ' An EOF charater was found in the input stream
        Case comEvEOF
            DoEvents
        ' There are SThreshold number of characters in the transmit buffer.
        Case comEvSend
            DoEvents
        ' A Break was received.
        Case comEventBreak
            DoEvents
        ' Framing Error
        Case comEventFrame
            DoEvents
        ' Data Lost.
        Case comEventOverrun
            DoEvents
        ' Receive buffer overflow.
        Case comEventRxOver
            DoEvents
        ' Parity Error.
        Case comEventRxParity
            DoEvents
        ' Transmit buffer full.
        Case comEventTxFull
        ' Unexpected error retrieving DCB]
        Case comEventDCB
            DoEvents
    End Select
End Sub
Private Sub tmrRead_Timer()
'MSComm1.Output = vbCrLf + vbCrLf
'MSComm1.Output = Chr(128)
End Sub
Private Sub txtMessage_KeyDown(KeyCode As Integer, Shift As Integer)
If Shift = 2 Or Shift = 4 Then RejectKeystroke = False Else RejectKeystroke = True
End Sub
Private Sub txtMessage_KeyPress(KeyAscii As Integer)
If RejectKeystroke Then
    KeyAscii = 0
End If
End SubThanks in advance..

I want to replicate the entire VB program as Java Program.
This has to be included in my project which i am doing in java.

Serial Ports using HyperV in Ubuntu guest OS

I need to run a terminal session (term) from within the guest OS, Ubuntu 12.04.3 LTS to a serial port on the Windows 8.1P host. In my case a USB to serial adapter that Windows has mapped to COM5.
I don't really know where to start.  In HyperV, under Settings, I see a Com1 and Com2 under hardware. The two options are None or Named pipe. Not all that clear what to do here.
Presumably this is what will be visible to Ubuntu as /dev/ttyXX   ??
Can anyone point the way to map a serial port into Ubuntu?   Or a suitable workaround?
Thanks.

"How can a VM be so cut off from the hardware like that?"
Well, for the most part, it's been a long time since I have even seen a machine with a serial port on it. It is so uncommon that one generally needs to buy an add-on card or do something like USB to serial. That trend has been going on for a
long time - that's why network based serial devices have tended to the solution for this. This is nothing new. Even Microsoft's Virtual Server, the precursor to Hyper-V (which was released five years ago) did not have access to serial ports.
Since you are asking in the Hyper-V forum, the answer is you can't get to a physical serial port on your host.
.:|:.:|:. tim

Serial port vi taking too much time to communicate?

i am using visa vis for serial communication the read vi takes too much time to give me the bytes at serial port.what should i do to decrease the delay?

You wouldn't happen to be specifying a byte count to read or setting read termination when a specific character is read would you? If you are, if you don't have the right number of bytes in the serial buffer or if the termination character is not seen, then VISA read will wait for the time specifed by the VISA timeout value. To fix the first problem, use the VISA Bytes at Serial Port function to determine how many bytes to read. In the second case, use a VISA property node to set Message Based Settings:Termination Character Enable to false and Serial Settingserial End Mode for Reads to none.

The "VISA Configure Serial Port" VI will only run at 9600 Baud

I have written a Serial Port monitor "RS232 RW.vi" that works for the most part. The problem is that it will not respond to alternate port configuration settings.... For instance: the default RS232 Serial port configuration is:
(COM1,9600 baud,8 data bits,1 Stop bit, None no parity)
As a test, I am using a Null Modem Cable to connect From my LabView Com1 port to another PC running RealTerm Serial Port Monitor.. Using my newly designed "RS232 RW.vi" With port settings of (COM1,9600 baud,8 data bits,1 Stop bit, None no parity), I can send and receive data back and forth all day long no problems....
However, if I configure the "RS232 RW.vi" port to any other configuration, such as (COM1,2400 baud ,7 data bits,1 stop bit, Odd parity).. It will not take the expected chances and continues to operate @ 9600 baud etc.
I then changed the "RS232 RW.vi" default settings to (2400,7,1,Odd)
it still refuses to deviate from (COM1, 9600,8,1,None...)
I also went into the Win XP Device Manager on the LabView system and manually configured Com1 to 2400,7,1,Odd
and still,.... the "RS232 RW.vi" will only operate @ 9600,8,1,None
Can anyone else test drive my VI and see if they have the same problem of not being able to see new changes in the Port configuration settings ..other than (COM1, 9600,8,1,None...).... ?
FYI.. Unfortunately my LabView is running on Version 6.0 so you may need to up-convert the attached vi
Solved!
Go to Solution.
Attachments:
RS232 RW.vi ‏102 KB

Instead of just appreciating the comments, you need to implement them.
Having the VISA close inside the loop is definitely the problem. And Crossrulz is 100% correct about the problem being that the serial port gets reset to the default baud rate after closing the port. Here is the proof.
Note that while you may have set the port settings manually in device manager, those settings are revised by the VISA driver. If you look in Measurement and Automation Explorer under Devices and Interfaces >> Serial and Parallel, you'll see the default settings that the VISA driver uses. If you change the setting there, your program will work the way you want. But that is not the correct fix. The correct fix is to get the VISA close out of the while loop.
The port settings are established in this order.
1. By the Windows device drivers.
2. By the VISA driver as established in MAX. Since you are useing VISA, these settings will automatically override #1.
3. By the port settings you set programmatically in your LabVIEW program.
Attachments:
Example_VI.png ‏18 KB

Serial port A has gone dead, B is ok, how to use it with rommon?

Good day,
the serial port A on E250 has gone dead. The communication is one-way, I can send, but no response is received. However serial port B is ok. Question is, how can I use port B for rommonitor/solaris install?
Thanks,

well, here's a thought... but i'm not sure how useful it will be to either of you if the system currently won't boot.
the openboot environment variables you're going to change are input-device and output-device
if you were at an ok> prompt, you could simply type 'setenv input-device ttyb', i think you'd also have to set the output-device :)
if you were booted into solaris, you could use the /usr/platform/<your platform here>/sbin/eeprom command to set the eeprom values, for both of you, your platform is sun4u, so you would type:
/usr/platform/sun4u/sbin/eeprom input-device=ttyb
likewise for output-device, you can check your eeprom settings by running eeprom without any arguments.
if you can't boot up currently... then... uh... crap... that's tough... if you can't get into it at all you're gonna have to call sun... probably want to replace that motherboard anyways...
fred

I pull fiftyfour bytes of data from MicroProcessor's EEPROM using serial port. It works fine. I then send a request for 512 bytes and my "read" goes into loop condition, no bytes are delivered and system is lost

I pull fiftyfour bytes of data from MicroProcessor's EEPROM using serial port. It works fine. I then send a request for 512 bytes and my "read" goes into loop condition, no bytes are delivered and system is lost

Hello,
You mention that you send a string to the microprocessor that tells it how many bytes to send. Instead of requesting 512 bytes, try reading 10 times and only requesting about 50 bytes at a time.
If that doesn�t help, try directly communicating with your microprocessor through HyperTerminal. If you are not on a Windows system, please let me know. Also, if you are using an NI serial board instead of your computer�s serial port, let me know.
In Windows XP, go to Start, Programs, Accessories, Communications, and select HyperTerminal.
Enter a name for the connection and click OK.
In the next pop-up dialog, choose the COM port you are using to communicate with your device and click OK.
In the final pop
-up dialog, set the communication settings for communicating with your device.
Type the same commands you sent through LabVIEW and observe if you can receive the first 54 bytes you mention. Also observe if data is returned from your 512 byte request or if HyperTerminal just waits.
If you do not receive the 512 byte request through HyperTerminal, your microprocessor is unable to communicate with your computer at a low level. LabVIEW uses the same Windows DLLs as HyperTerminal for serial communication. Double check the instrument user manual for any additional information that may be necessary to communicate.
Please let me know the results from the above test in HyperTerminal. We can then proceed from there.
Grant M.
National Instruments

How can I write bits through the COM1 serial port?

I'm trying to write bits through the serial port COM1.
Labview "Write VI" only writes everything in string. It seems. How can I write bit by bit through COM1?
Thank you,
Van

Serial transmission (COM port) protocol requires sending a group of bits at one time. You cannot just send one bit. Standard COM port settings must be either 7 or 8 data bits, 1 or 2 stop bits, etc... You have to group your bits 7 or 8 at a time. You could probably send a 0 byte or a 1 byte. This would be like sending 0000 0000 for a low bit and 0000 0001 for a high bit. Your receiving end would have to know how to interpret what you are sending if you choose this method. Of course you have to convert your byte into a string before sending to COM port. Wire a U8 data type to a Build Array input. Then wire the array output to a Byte Array to String input. The output of this function will be the character representation of your byte suitable for sending acr
oss a serial port.
- tbob
Inventor of the WORM Global

Rs485 and VISA Configure Serial Port.vi ?

I'm given the following spec:
RS485, full duplex asynchronous, 19.2K baud, 1 start bit, 1 stop bit, 1 parity bit, and 8 data bits.
VISA Confgiure Serial Port.vi does not have input for 1 start bit and parity choices are none, even, odd, mark, space.
What should my settings bit for this to work?

Since the VISA Confgiure Serial Port.vi does not have an input for the start bit you can just ignore this. For the parity bit, your instrument should give more information. For example, two of the choices are even or odd. These are both one parity bit, so your instrument needs to define whether it is odd or even. It should say on the spec sheet.
Hope this helps!
JenK

Serial port settings

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