Filter serial port input
Hi All,
I am sending in a signal from a pic to labview. I am sampling at 480 hz. I can plot it perfectly(i just use a time scaler of 1/480 in the graph) but I'd also like to show three seperate plots... narrowband filter at 0-5 hz, 5-8, and 8 - 30. But I can't seem to implement even a sample filter, I get the message Digital Filter Design Toolkit: The filter object is invalid. I'm not sure what this is about but this isn't totally necessary to my project but I'm doing EEG waves and separating the signal into three narrowbanded results would be great. Any ideas would be greatly appreciated!
Attachments:
usart_and_filter.vi 74 KB
Hi,
Thanks for your post and I hope your well today.
Ive noticed you've not received any support thus far.
I would like to look into this issue tomorrow (when im in the UK office), to see what I can find out.
Are you still having an issue, an update would be great!
What version of LabVIEW are you using? and which toolkit are you using - im assuming you have the DFDT toolkit installed.
Kind Regards,
Kind Regards
James Hillman
Applications Engineer 2008 to 2009 National Instruments UK & Ireland
Loughborough University UK - 2006 to 2011
Remember Kudos those who help!
Similar Messages
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Java applets in a browser, and Serial port input
I know that there is a special package for serial port input in java. (java.Comm.SerialPort)
What I am trying to figure out before a final decision on design is made, is if there is anyway of reading serial port input into a java applet that is running inside of a browser.
I have found lots of reference to Serial port input, but nothing that really goes in the direction that I am lookind for.
Any little tid bits of information pertaining to this would be greatly appreciated.
CuervoYou should also consider that applets are not allowed to access their client system's hardware without being signed; in other words, the user must agree (by clicking a button) to disable the applet security features. Why would you use an applet to do this? Applets are meant to be an extension of a website. You should use an application in this situation.
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Serial port: Input/output signal errantly combined
I am currently in the process of using LabView to replace another user interface for a scientific instrument.
LabView is connected to this instrument through a serial port. The instrument streams 25 bytes of binary data every second to the computer. I can read the binary string (VISA Read) and save contiuously to disk using a while loop. In addition, there are a few instructions I can send to the instrument that will do various functions (start logging, turn LEDs on/off, etc). I can successfully send these instructions to the instrument using the previous interface, and in a stand-alone vi using VISA Write, but when I place the VISA Write function into the larger interface vi, signals go haywire. Specifically, there are two separate LEDs that I can toggle with two different commands, but when in the larger interface vi, both commands toggle the same LED. Also, it appears that the singal I send to the instrument (a single ASCII character) immediately bounces back to the computer into the 25 bytes of streaming binary data. In other words, after I press the LED "on" key, one column of my streaming data changes when it is not supposed to (ex: after Binary to ASCII conversion, it changes from a single digit to a twenty digit value).
Initially, I thought the problem was the sequence of VISA Read/Write. In the current configuration, I read all data, then allow for Write commands. Both the VISA functions are within the same While loop to continuously monitor the data. Is it possible the Write signal output is not leaving the while loop and being read as input? What would make the instrument read two different commands as the same one? My goal is to run an interface that displays the streaming data as ASCII, and allows for a few different toggle options while the interface is running - is there are more efficient/elegant way than a while loop?
~Going Bananas
Solved!
Go to Solution.New replies now in gray.
CodeMunkee wrote:
1. If you keep giving me good advice like this, I'll be tempted to change the background to Baltimore prison purple.
I'll ignore this statement.
2. The buffer now lives outside the loop. I understand clearly. Part of the problem might be my instrument - when I cycle power the 19 digit number that was 'echoed' disappears. Forget about that display stuff, it works properly - I accidentally removed the time delay when editing the vi. But you do bring up an interesting point...
Without the delay, the loop ran much faster. If the bytes weren't at the port, the read statement would have returned nothing when it read zero bytes, thus blanking out the indicator rather quickly.
Yes, Hexadecimal display shows 04 to indicate the end of the 25-byte data sample.
Doing a bytes at port read is not always a good idea. If not all the bytes had arrived yet when you ask for the read, you won't get all the data. The remaining data being sent in that stream from the instrument will show up at the front of the buffer on the next read command.
While this isn't a common occurence, it does happen. How can I prevent this from ever happening?
Since you know each commands ends with a hex 04 (ASCII character for EOT), you could enable the termination character when you configure the serial port. Set the termination character to be 4. Then when you execute the VISA read, read a large number of bytes such as 25 or more. The read will terminate at either the timeout, the requested number of bytes, or when the termination character is read. With this setup, you could eliminate the wait statement and also not request the number of bytes as the port. The VISA read will control the pacing of the loop. Any extra bytes after the termination character are part of the next frame of data and will wait around until the next time you read the VISA port.
3. Implementing your ideas for the latch button works better. I am still encountering issues with these commands however. Attached is the new vi. There are two commands I want to send, 't' turns on the LED light (they blink for 30 sec then time out), and the latch works perfectly for that, 'p' turns on the magnetometer light (an additional 'p' is required to turn it off), but I cannot get the command sent to the mag while the loop is running. It turns on either at the beginning of the vi, or at the end of the vi (after Finish button is pressed). This leads me to think the command 'p' is stuck inside the loop. I tried adding another film strip (see attached vi) for the toggles to force the issue, but it didn't work. Additionally, the 'p' command effectively works as a 't' command, and the LED lights begin to blink when I press the 'p' button. This isn't supposed to happen, and leads me to believe the 'p' command does in fact exit the loop but in the wrong manner.
The "film strip" is another frame of a flat sequence structure. It enforces the order of execution. The next frame can't execute until everything in the prior frame has completed. It isn't necessary in your case because the Error and VISA wires determine the order of execution with respect to the other VISA statements. But it shouldn't hurt.
There is no reason the "p" case structure should behave any differently than the "t" case structure. Although you should wire the error wire through in the False case of the "p" structure like you did for the "t" structure. There is no "exiting of the loop" in either case. The loop runs until the stop button is pressed. I would check the manual to see that t and p commands do what you think they should do. Do they need a termination character of their own when they are sent? Should they be upper case letters rather than lower case? You can run NI Spy on your serial port and see the operations occurring with it and see the data coming in and what data is going out. I would be suspicious that the device is not handling the command properly.
Any ideas? I think I've tried to put the toggle buttons outside the loop before, but then could only toggle once before the loop took over. Ideally, these toggles would be available at any time while the data is streaming, so therefore inside the loop?
The toggle buttons need to be within the loop so that they can be read on every iteration of the loop. Outside the loop, as you discovered, they are only read once at the very beginning before the loop is started.
4. Thank you for the suggestion about the Selection Mode for the Open/Create File option. It is annoying to create a file first. I made the change, but I still get error messages when I use a file that does not yet exist. LabView takes me to the first Open/Create/Replace vi when the error occurs. Is there something else I must do?
On the open file VI, there is an input that is Open as default when unwired. Create a constant there and change to Replace or Create.
Remember, if you have any questions about the way LabVIEW is handling something with serial ports, close the port within LabVIEW. Open Hyperterminal and try the commands from there.
Message Edited by Ravens Fan on 01-13-2009 03:55 PM -
Detect input signs at serial port
Hello,
It is posible using Lingo detect input signs at computer serial port??
Thanks for your helpThis is certainly possible - check the Mile High Table for xtras that can help with serial communication
-
Using a PS/2 keyboard on a Sparc workstation through the serial port
We have recently migrated an application that used to run on a PC, to now run on a Sparc Workstation. This is a SunBlade 1500, running Solaris 8. The application is running in a dedicated console which has a fitted keyboard and trackerball that have PS/2 connectors and cannot be changed.
We need a way of connecting the PS/2 keyboards to the serial ports of the Sparc workstation. We already have a piece of software that will read ascii values from the serial port so we definately want to go through the serial ports.
Can someone please suggest what converters will be required to get the output of the keyboard and trackerball as ascii input to the serial port.Actually, that's not a bit perverse, at all.
Jonathan's suggestion is a standard method of connecting to a server.
(null cable between the computer serial ports)
... see the Solaris man pages.
man tip
TeraTerm and Hyperterminal are customarily used on a PC running some dialect of Windows.
The 'tip' command is all that's necessary between Solaris systems.
PS/2 is not a serial connection, but is a keyboard/mouse interface 'invented' by IBM when they offered their XT-class PS/2 line of desktop systems, back in the 1980's.
I found this next link by using Google:
http://members.chello.at/theodor.lauppert/computer/ps2/
The smaller DIN ports were more compact than the AT-class keyboard ports and the mouse moved from a serial port to a dedicated mouse port.
Serial communication devices are not keyboards, per se,
and keyboards are not serial communication devices.
You need other hardware in between to translate what the human being sends, and another computer is a common method to accomplish that translation.
Having said all that ...
Since you cannot change the dedicated console hardware,
I suggest you go to the manufacturer of that console equipment
and have them suggest some sort of serial-to-serial interface lash-up. -
How do I process serial port strings as bits
In response to my commands, my instrument is sending bytes to my serial
port. In one instance, 2 bytes are received. I want to treat these 2 bytes
as a group of 16 bits.
The VISA and Compatibility Serial functions return these bytes from the
serial port to Labview clearly labelled a "string".
Everything I can find in the way of Labview functions and .vis don't want to
do bit twiddling, bit swapping, and bit dropping, with "string" data.
I thought "hex string to number" could be used here, but I can't find a way.
The 2 Bytes in question can be represented as hex, but the data are not the
ASCII codes for the hex representation of a binary number, they are the
binary number. This "hex string to number" seems to want ASCII c
odes.
You can feed a hex number typed into a "control" box wired into "hex string
to number" and you get a meaningful number. You can feed the 2 bytes from
the serial port into an "indicator" set to read in hex and you get a hex
number that is a correct representation. But that is Labview handing them
around to itself. I need to get my "hands" on them.
I can't feed those same bytes that show up as a correct hex representation
in an indicator into the "hex string to number" or anything else, so far,
and get a number that is useful for further processing.
I thought "variant to data", but I can't find enough reference material to
understand how to use it. A boolean array seems like a bit of a weird
approach, so I thought I'd ask before I looked into that.
I'm used to dealing directly with binary numbers on the processor stack, I
call them whatever I want, and turn them into anything I feel like.
I'm sure I'm staring the solution in the face, but I can't find any way to
persuade
Labview to treat this "string" data as 16 bits.
I've got the 16 bits, which is better than not having them, but I don't have
much hair left.duh, well I finally discovered the "Unflatten from String" function. A guy
just feeds in the bytes he's collected from his serial port that Labview
thinks are a "string", and out come lovely little unsigned 16 bit numbers,
or whatever other type of number he wants to turn the bytes into. And there
are great little bit twiddlers available after that, like "swap bytes", and
you can mask out bits with the logic operators, why this is fun. There's
nothing like being a moron...... fly me to the moon...................
"David Lewis" wrote in message
news:[email protected]..
> The two bytes would come from a serial port read.vi in Labview, classed as
a
> string. For instance, D3 and 02. The output wou
ld swap the two bytes,
i.e.
> to 02 and D3, consider the two swapped bytes as 16 bits, drop the six most
> significant bits, and output the ten bits that are left as an integer
> classed by Labview as some kind of number, not a string.
>
> Your example StringToBits_Converter.vi I found on the ni.com site
> unfortunately gives an error message and refuses to open on my system
saying
> it comes from a newer version of Labview 6 than I am running. Mine says
> 6.0.1b3. Thank you very much anyway.
>
> "FightOnSCTrojan" wrote in message
> news:[email protected]..
> > In another words, you want to create a VI in which the input is 2
> > strings (i.e. AB) and the output is the converted array bits (e.g.
> > 1010101010101010)?
>
> -
I am working on a wireless vital sign monitor. I have 3 signals; heart rate and temperature. I filter and amplify the signals before converting them into digital form. I then pass them via MAX232 before passing them to RS232 serial cable.
I am therefore working on a program to receive the combined signal and separate them.
I have come across serial read and write examples on ni.com but am looking for one where I can actually separate combined signals and display them separately.Reading the serial port will give you a string. How you divide the channels depends on how the data was formatted before it was sent over the serial channel.
If you are designing the instrument, as it seems from your query, then you can set up any form you wish. If your data is always floating point numeric, you could use space or tab characters to separate data words. You could use and XML format. If the instrument is provided by a vendor, contact them for the protocol.
If tabs are used between words and returns between sets of readings, the resutlant string can be interpretted by the Spreadsheet String to Array function in LV.
Things to avoid are characters often used by serial communications systems as control characters. Carraige returns are
often used as command terminators by serial protocols, but may also be used by the port.
Lynn -
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. -
How do I use serial port read and show text, but not have it scroll off screen?
I am new-ish/returning amateur user of Labview and I am trying to edit the example VI "Advanced serial write and read VI" that is part of dev suite 2012. I need to use the string box to show ALL text received from serial port, always appending and only rolls off screen when more real data arrives at serial port.
What is actually happening is as more bytes (or no bytes AT ALL!) arrive during read time, current text rolls off the string box. Even when 0 bytes are received, screen is blanked out. I am not very familiar with functions locations and even worse at understanding obscure references to functions, so please keep replies very basic so I can follow.
Just to be clear, I need the string window to behave like hyperterm does-always shows data and it is not pushed out of window arbitrarily.
Thanks,
Steve
Solved!
Go to Solution.OK- lets start back at the beginning. I have a few questions...
WHy does incoming txt get placed at top of txt box and then scroll up? why would it make more sense to input at the bottom and scroll toward the top. I have created this huge txt box that appears to be impossible to use.
I have attached example of txt boxes I have tried, and pic of VI I have edited. Bad marks for uglyness....
Attachments:
Capture_VI.JPG 117 KB
Capture_VI2.JPG 133 KB -
Is it possible to choose the serial port if only the run time engine is installed
I have an application, which communicates over the serial port. When I use the full version of Labview I can change the serial port without any problem from Com1 to Com2 (similar to the example “Hardeware input output -> serial -> Labview serial vi"). When I build an application and try to run this program on a computer where only the run time engine 6.1 is installed, it is not possible to choose the serial port. Since there is no “Measurement and Automation Explorer” available on the run time engine and no directory C:\VXIpnp is created, when the run time engine is installed, I do not see a way, how I can satisfy the computer with the information it needs for configuring
the different ports. Any suggestions?Hi Daniel,
Before LV6.1 there was LV5.1 In LV5.1 the way to Spedify a resource was to use a string control with correct VIsa Resource Class identifier. For eg. "GPIB0::11" or "ASRL1::INSTR". With Introduction of VISA Resource Name Control and linking with MAX, These names are Available from Pull Down List and Can be Aliased, meaning ASRL1 which is Serial Port 1 can be called COM1 and so on. However the old method still works with all 6.1 Controls. Only thing is you have to make sure you Dont Conflict the Class Names ie Use "GPIB::.." instead of "ASRL..." when addressing Serial Port VI's.
To solve your Problem I would Build a Menu ring with COM1 to COM4 in the Pull Down List.
Next, If I use the Traditonal Serial Port VI wich accepts the Integer as Seria
l Port #. I just Wire the Menu Ring to this VI.(Remember COM1 is 0, COM2 is 1 for this VI)
If I use VISA Config Serial Post. I build an Array Constant with Corresponding VISA Class Names So in our case a String Array Constant of 4 elements "ASRL1::INST" to "ASRL4::INST". I Use Index Array Function With the Index Wired to my Menu Ring. The Array Input Terminal Wired to the Array Constant. The Output of this Array will be correct Visa Class Name Based on slection of my Menu Ring. I can Wire this as Input to my VISA Config Serial Port Vi.
I have attached a Small VI to Illustrate this.
Drawback: You must Predefine what Ports you will Want to Use. Basically you define all the cases.
I hope this Answers your Q!
Good Luck
Mache
Good Luck!
Mache
Attachments:
Serial_Port_Select.vi 36 KB -
I have a gilsson usb to serial port bi directional adapter cable which uses the Prolific pl-2303 chipset. I am attempting to use this cable to interface a Mac Mini with a Harsper PDP plasma television.
I am attempting to control the functions of the television via the serial port on the television. i.e. Turn on, input, volume, etc.
What I need is software, or source code that would allow me to send hexidecimal commands to the television and receive the task completed codes.ZTerm will allow serial communications. Get it to ensure that throughput is happening as expected.
RealBasic will allow you to roll your own with a fair amount of ease.
A long time ago I used the above to communicate with my cellphone to send and receive text messages via the serial port, so I know it can work. Understanding the protocols is the difficult part... -
How to access the serial port on sdk 3.1.3 ?
Hi all,
I know that accessing serial port is not possible on firmware 2.x for non jailbroken iPhones.
But what about firmware 3.0?
Apple has focused firmware 3.0 on accessories, through bluetooth or through serial port. So, accessing serial port should be possible.
But I can't find any documentation / sample code for that.
Would you please help me?
Regards,
Alx
PS: I tried to read the port /dev/cu.iap and get this message:
Error opening serial port /dev/cu.iap - Permission denied(13).
Looks bad.Yes I am enregistred in the Mad For iPod program?
And I try to communique with my accessorie
So the Code
+*// SerialPortsModuleAppDelegate.m*+
+*// SerialPortsModule*+
+*// Created by BPO iMac on 08/02/10.*+
+*// Copyright _MyCompanyName_ 2010. All rights reserved.*+
+*#import "SerialPortsModuleAppDelegate.h"*+
+*#import <fcntl.h>*+
+*@implementation SerialPortsModuleAppDelegate*+
+*@synthesize window;*+
+*- (void)applicationDidFinishLaunching:(UIApplication *)application {*+
+*// Override point for customization after application launch*+
+*[window makeKeyAndVisible];*+
+* portSerie = [SerialManager alloc];*+
+* [portSerie init];*+
+* int nb_port;*+
+* nb_port = [portSerie findRS232Ports];*+
+* NSString path_port;+
+* path_port = [NSString alloc];*+
+* int num_port;*+
+* if(nb_port!=0)*+
+* {*+
+* num_port=0;*+
+* path_port=[portSerie pathAtIndex:num_port];*+
+* int resultat= [portSerie openInput:path_port baudrate:9600 bits:8 parity:0 stopbits:1 flags:O_RDONLY];*+
+* if(resultat==-1)*+
+* {*+
+* NSLog(@"Communication Error");*+
+* }*+
+* resultat= [portSerie openOutput:path_port baudrate:9600 bits:8 parity:0 stopbits:1];*+
+* if(resultat==-1)*+
+* {*+
+* NSLog(@"Communication Error");*+
+* }*+
+* }*+
+* [path_port release];*+
+* *+
+*- (void)dealloc {*+
+*[window release];*+
+*[super dealloc];*+
@end
+*// SerialPortsModuleAppDelegate.h*+
+*// SerialPortsModule*+
+*// Created by BPO iMac on 08/02/10.*+
+*// Copyright _MyCompanyName_ 2010. All rights reserved.*+
+*#import <UIKit/UIKit.h>*+
+*#import "SerialManager.h"*+
+*@interface SerialPortsModuleAppDelegate : NSObject <UIApplicationDelegate> {*+
+*UIWindow window;+
+* SerialManager portSerie;+
+*@property (nonatomic, retain) IBOutlet UIWindow window;+
@end
+*// SerialManager.m*+
+*// K3 Tools*+
+*// Created by Kok Chen on 4/28/09.*+
+*// Copyright 2009 Kok Chen, W7AY. All rights reserved.*+
+*#import "SerialManager.h"*+
+*#include <unistd.h>*+
+*#include <termios.h>*+
+*#include <sys/ioctl.h>*+
+*#include <IOKit/IOKitLib.h>*+
+*#include <IOKit/serial/IOSerialKeys.h>*+
+*#import <fcntl.h>*+
+*#import <UIKit/UIKit.h>*+
+*@implementation SerialManager*+
+*- (id)init*+
+* self = [ super init ] ;*+
+* if ( self ) {*+
+* termiosBits = -1 ;*+
+* inputfd = outputfd = -1 ;*+
+* useTermiosThread = NO ;*+
+* needsNotification = NO ;*+
+* termioLock = [ [ NSLock alloc ] init ] ;*+
+* }*+
+* return self ;*+
+*static int findPorts( CFStringRef *stream, CFStringRef *path, int maxDevice, CFStringRef type )*+
+*kernreturnt kernResult ;*+
+*machportt masterPort ;*+
+* ioiteratort serialPortIterator ;*+
+* ioobjectt modemService ;*+
+*CFMutableDictionaryRef classesToMatch ;*+
+* CFStringRef cfString ;*+
+* int count ;*+
+*kernResult = IOMasterPort( MACHPORTNULL, &masterPort ) ;*+
+*if ( kernResult != KERN_SUCCESS ) return 0 ;*+
+* *+
+*classesToMatch = IOServiceMatching( kIOSerialBSDServiceValue ) ;*+
+*if ( classesToMatch == NULL ) return 0 ;*+
+* *+
+* // get iterator for serial ports (including modems)*+
+* CFDictionarySetValue( classesToMatch, CFSTR(kIOSerialBSDTypeKey), type ) ;*+
+*kernResult = IOServiceGetMatchingServices( masterPort, classesToMatch, &serialPortIterator ) ;*+
+* // walk through the iterator*+
+* count = 0 ;*+
+* while ( ( modemService = IOIteratorNext( serialPortIterator ) ) ) {*+
+* if ( count >= maxDevice ) break ;*+
+*cfString = IORegistryEntryCreateCFProperty( modemService, CFSTR(kIOTTYDeviceKey), kCFAllocatorDefault, 0 ) ;*+
+*if ( cfString ) {*+
+* stream[count] = cfString ;*+
+* cfString = IORegistryEntryCreateCFProperty( modemService, CFSTR(kIOCalloutDeviceKey), kCFAllocatorDefault, 0 ) ;*+
+* if ( cfString ) {*+
+* path[count] = cfString ;*+
+* count++ ;*+
+* }*+
+* }*+
+*IOObjectRelease( modemService ) ;*+
+* IOObjectRelease( serialPortIterator ) ;*+
+* return count ;*+
+*// return number of ports*+
+*- (int)findPorts:(CFStringRef)type*+
+* CFStringRef cstream[64], cpath[64] ;*+
+* int i ;*+
+* *+
+* numberOfPorts = findPorts( cstream, cpath, 64, type ) ;*+
+* for ( i = 0; i < numberOfPorts; i++ ) {*+
+* stream = [ [ NSString stringWithString:(NSString*)cstream ] retain ] ;*+
+* CFRelease( cstream ) ;*+
+* path = [ [ NSString stringWithString:(NSString*)cpath ] retain ] ;*+
+* CFRelease( cpath ) ;*+
+* }*+
+* return numberOfPorts ;*+
+*- (int)findPorts*+
+* return [ self findPorts:CFSTR( kIOSerialBSDAllTypes ) ] ;*+
+*- (int)findModems*+
+* return [ self findPorts:CFSTR( kIOSerialBSDModemType ) ] ;*+
+*- (int)findRS232Ports*+
+* return [ self findPorts:CFSTR( kIOSerialBSDRS232Type ) ] ;*+
+*- (NSString)streamAtIndex:(int)n+
+* if ( n < 0 || n >= numberOfPorts ) return nil ;*+
+* return stream[n] ;*+
+*- (NSString)pathAtIndex:(int)n+
+* if ( n < 0 || n >= numberOfPorts ) return nil ;*+
+* return path[n] ;*+
+*// common function to open port and set up serial port parameters*+
+*static int openPort( NSString *path, int speed, int bits, int parity, int stops, int openFlags, Boolean input )*+
+* int fd, cflag ;*+
+* struct termios termattr ;*+
+* *+
+* fd = open( [ path cStringUsingEncoding:NSASCIIStringEncoding], openFlags ) ;*+
+* if ( fd < 0 ) return -1 ;*+
+* *+
+* // build other flags*+
+* cflag = 0 ;*+
+* cflag |= ( bits == 7 ) ? CS7 : CS8 ; // bits*+
+* if ( parity != 0 ) {*+
+* cflag |= PARENB ; // parity*+
+* if ( parity == 1 ) cflag |= PARODD ;*+
+* }*+
+* if ( stops > 1 ) cflag |= CSTOPB ;*+
+* *+
+* // merge flags into termios attributes*+
+* tcgetattr( fd, &termattr ) ;*+
+* termattr.c_cflag &= ~( CSIZE | PARENB | PARODD | CSTOPB ) ; // clear all bits and merge in our selection*+
+* termattr.c_cflag |= cflag ;*+
+* *+
+* // set speed, split speed not support on Mac OS X?*+
+* cfsetispeed( &termattr, speed ) ;*+
+* cfsetospeed( &termattr, speed ) ;*+
+* // set termios*+
+* tcsetattr( fd, TCSANOW, &termattr ) ;*+
+* return fd ;*+
+*- (int)openInput:(NSString*)pathname baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops flags:(int)openFlags*+
+* return ( inputfd = openPort( pathname, speed, bits, parity, stops, openFlags, YES ) ) ;*+
+*- (int)openInput:(NSString*)pathname baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops*+
+* return ( inputfd = openPort( pathname, speed, bits, parity, stops, ( O_RDONLY | O_NOCTTY | O_NDELAY ), YES ) ) ;*+
+*- (int)openOutput:(NSString*)pathname baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops flags:(int)openFlags*+
+* return ( outputfd = openPort( pathname, speed, bits, parity, stops, openFlags, NO ) ) ;*+
+*- (int)openOutput:(NSString*)pathname baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops*+
+* return ( outputfd = openPort( pathname, speed, bits, parity, stops, ( O_WRONLY | O_NOCTTY | O_NDELAY ), NO ) ) ;*+
+*- (void)closeInput*+
+* if ( inputfd > 0 ) close( inputfd ) ;*+
+*- (void)closeOutput*+
+* if ( outputfd > 0 ) close( outputfd ) ;*+
+*- (int)inputFileDescriptor*+
+* return inputfd ;*+
+*- (int)outputFileDescriptor*+
+* return outputfd ;*+
+*- (int)getTermios*+
+* int bits ;*+
+* *+
+* if ( inputfd > 0 ) {*+
+* [ termioLock lock ] ;*+
+* ioctl( inputfd, TIOCMGET, &bits ) ;*+
+* [ termioLock unlock ] ;*+
+* return bits ;*+
+* }*+
+* return 0 ;*+
+*- (void)setRTS:(Boolean)state*+
+* int bits ;*+
+* if ( inputfd > 0 ) {*+
+* [ termioLock lock ] ;*+
+* ioctl( inputfd, TIOCMGET, &bits ) ;*+
+* if ( state ) bits |= TIOCM_RTS ; else bits &= ~( TIOCM_RTS ) ;*+
+* ioctl( inputfd, TIOCMSET, &bits ) ;*+
+* [ termioLock unlock ] ;*+
+* }*+
+*- (void)setDTR:(Boolean)state*+
+* int bits ;*+
+* if ( inputfd > 0 ) {*+
+* [ termioLock lock ] ;*+
+* ioctl( inputfd, TIOCMGET, &bits ) ;*+
+* if ( state ) bits |= TIOCM_DTR ; else bits &= ~( TIOCM_DTR ) ;*+
+* ioctl( inputfd, TIOCMSET, &bits ) ;*+
+* [ termioLock unlock ] ;*+
+* }*+
+*// IO Notifications*+
+*// prototype for delegate*+
+*- (void)port:(NSString*)name added:(Boolean)added*+
+* if ( delegate && [ delegate respondsToSelector:@selector(port:added:) ] ) [ delegate port:name added:added ] ;*+
+*// this is called from deviceAdded() and deviceRemoved() callbacks*+
+*- (void)portsChanged:(Boolean)added iterator:(ioiteratort)iterator*+
+* ioobjectt modemService ;*+
+* CFStringRef cfString ;*+
+* while ( ( modemService = IOIteratorNext( iterator ) ) > 0 ) {*+
+* cfString = IORegistryEntryCreateCFProperty( modemService, CFSTR( kIOTTYDeviceKey ), kCFAllocatorDefault, 0 ) ;*+
+* if ( cfString ) {*+
+* [ self port:(NSString*)cfString added:added ] ;*+
+* CFRelease( cfString ) ;*+
+* }*+
+* IOObjectRelease( modemService ) ;*+
+* }*+
+*// callback notification when device added*+
+*static void deviceAdded(void *refcon, ioiteratort iterator )*+
+* ioobjectt modemService ;*+
+* *+
+* if ( refcon ) [ (SerialManager*)refcon portsChanged:YES iterator:iterator ] ;*+
+* else {*+
+* while ( modemService = IOIteratorNext( iterator ) ) IOObjectRelease( modemService ) ;*+
+* }*+
+*static void deviceRemoved(void *refcon, ioiteratort iterator )*+
+* ioobjectt modemService ;*+
+* *+
+* if ( refcon ) [ (SerialManager*)refcon portsChanged:NO iterator:iterator ] ;*+
+* else {*+
+* while ( modemService = IOIteratorNext( iterator ) ) IOObjectRelease( modemService ) ;*+
+* }*+
+*- (void)startNotification*+
+* CFMutableDictionaryRef matchingDict ;*+
+* *+
+* notifyPort = IONotificationPortCreate( kIOMasterPortDefault ) ;*+
+* CFRunLoopAddSource( CFRunLoopGetCurrent(), IONotificationPortGetRunLoopSource( notifyPort ), kCFRunLoopDefaultMode ) ;*+
+* matchingDict = IOServiceMatching( kIOSerialBSDServiceValue ) ;*+
+* CFRetain( matchingDict ) ;*+
+* CFDictionarySetValue( matchingDict, CFSTR(kIOSerialBSDTypeKey), CFSTR( kIOSerialBSDAllTypes ) ) ;*+
+* *+
+* IOServiceAddMatchingNotification( notifyPort, kIOFirstMatchNotification, matchingDict, deviceAdded, self, &addIterator ) ;*+
+* deviceAdded( nil, addIterator ) ; // set up addIterator*+
+* IOServiceAddMatchingNotification( notifyPort, kIOTerminatedNotification, matchingDict, deviceRemoved, self, &removeIterator ) ;*+
+* deviceRemoved( nil, removeIterator ) ; // set up removeIterator*+
+*- (void)stopNotification*+
+* if ( addIterator ) {*+
+* IOObjectRelease( addIterator ) ;*+
+* addIterator = 0 ;*+
+* }*+
+* if ( removeIterator ) {*+
+* IOObjectRelease( removeIterator ) ;*+
+* removeIterator = 0 ;*+
+* }*+
+* if ( notifyPort ) {*+
+* CFRunLoopRemoveSource( CFRunLoopGetCurrent(), IONotificationPortGetRunLoopSource( notifyPort ), kCFRunLoopDefaultMode ) ;*+
+* IONotificationPortDestroy( notifyPort ) ;*+
+* notifyPort = nil ;*+
+* }*+
+*// prototype for delegate or subclass*+
+*- (void)controlFlagsChanged:(int)termbits*+
+* if ( delegate && [ delegate respondsToSelector:@selector(controlFlagsChanged:) ] ) [ delegate controlFlagsChanged:termbits ] ;*+
+*- (void)termiosThread*+
+* NSAutoreleasePool *pool = [ [ NSAutoreleasePool alloc ] init ] ;*+
+* int termbits ;*+
+* while ( 1 ) {*+
+* if ( useTermiosThread == NO ) break ;*+
+* if ( inputfd > 0 ) {*+
+* if ( [ termioLock tryLock ] ) {*+
+* ioctl( inputfd, TIOCMGET, &termbits ) ;*+
+* if ( termiosBits != termbits ) [ self controlFlagsChanged:termbits ] ;*+
+* termiosBits = termbits ;*+
+* [ termioLock unlock ] ;*+
+* }*+
+* [ NSThread sleepUntilDate:[ NSDate dateWithTimeIntervalSinceNow:0.25 ] ] ;*+
+* }*+
+* else {*+
+* [ NSThread sleepUntilDate:[ NSDate dateWithTimeIntervalSinceNow:1.0 ] ] ;*+
+* }*+
+* }*+
+* [ pool release ] ;*+
+*// If delegate is set, setDelegate also starts a termiosThread if delegate responds to -controlFlagsChanged:*+
+*- (void)setDelegate:(id)object*+
+* delegate = object ;*+
+* if ( delegate == nil ) {*+
+* useTermiosThread = NO ;*+
+* if ( needsNotification ) {*+
+* needsNotification = NO ;*+
+* [ self stopNotification ] ;*+
+* }*+
+* }*+
+* else {*+
+* if ( [ delegate respondsToSelector:@selector(controlFlagsChanged:) ] ) {*+
+* useTermiosThread = YES ;*+
+* [ NSThread detachNewThreadSelector:@selector(termiosThread) toTarget:self withObject:nil ] ;*+
+* } *+
+* if ( [ delegate respondsToSelector:@selector(port:added:) ] ) {*+
+* needsNotification = YES ;*+
+* [ self startNotification ] ;*+
+* }*+
+* }*+
+*- (id)delegate*+
+* return delegate ;*+
@end
+*// SerialManager.h*+
+*// K3 Tools*+
+*// Created by Kok Chen on 4/28/09.*+
+*// Copyright 2009 Kok Chen, W7AY. All rights reserved.*+
+*//#import <Cocoa/Cocoa.h>*+
+*#import <Foundation/Foundation.h>*+
+*#import <UIKit/UIKit.h>*+
+*#import <CoreData/CoreData.h>*+
+*//#import <IOKit/IOKitLib.h>*+
+*//#import <IOKitLib.h>*+
+*#include <IOKit/IOKitLib.h>*+
+*typedef int FileDescriptor ;*+
+*@interface SerialManager : NSObject {*+
+* NSLock *termioLock ;*+
+* FileDescriptor outputfd ;*+
+* FileDescriptor inputfd ;*+
+* id delegate ;*+
+* // serial ports in system*+
+* NSString *stream[64] ;*+
+* NSString *path[64] ;*+
+* int numberOfPorts ;*+
+* *+
+* // termios*+
+* int termiosBits ;*+
+* Boolean useTermiosThread ;*+
+* *+
+* // IO notifications*+
+* IONotificationPortRef notifyPort ;*+
+* ioiteratort addIterator, removeIterator ;*+
+* Boolean needsNotification ;*+
+*- (void)setDelegate:(id)sender ;*+
+*- (int)findPorts ;*+
+*- (int)findModems ;*+
+*- (int)findRS232Ports ;*+
+*- (NSString*)streamAtIndex:(int)n ;*+
+*- (NSString*)pathAtIndex:(int)n ;*+
+*- (FileDescriptor)openInput:(NSString*)path baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops ;*+
+*- (FileDescriptor)openInput:(NSString*)path baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops flags:(int)openFlags ;*+
+*- (FileDescriptor)openOutput:(NSString*)path baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops ;*+
+*- (FileDescriptor)openOutput:(NSString*)path baudrate:(int)speed bits:(int)bits parity:(int)parity stopbits:(int)stops flags:(int)openFlags ;*+
+*- (void)closeInput ;*+
+*- (void)closeOutput ;*+
+*- (FileDescriptor)inputFileDescriptor ;*+
+*- (FileDescriptor)outputFileDescriptor ;*+
+*- (int)getTermios ;*+
+*- (void)setRTS:(Boolean)state ;*+
+*- (void)setDTR:(Boolean)state ;*+
+*- (void)setDelegate:(id)object ;*+
+*- (id)delegate ;*+
+*// delegates*+
+*- (void)port:(NSString*)name added:(Boolean)added ;*+
+*- (void)controlFlagsChanged:(int)termbits ;*+
@end
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Well I am new to labview, my question might of beginner's level but i have searched the forums and didnt find content regarding it. Kindly help me through it as i am really stuck in it for last three days.
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