Solved

vb com port settings

Posted on 2006-11-08
9
163 Views
Last Modified: 2010-04-30
I am writing a vb application that uses com ports.
For some reason I get some errors when I run it.
Not vb errors, but I was getting the wrong responses from the device
I was talking to.

When I go to my control panel->System->device manager->Com Port->Port Settings->Advanced
Then I slide the 2 sliders all the way to the left the program works.

Is there any way to make this setting programmatically?
0
Comment
Question by:jackjohnson44
  • 4
  • 3
  • 2
9 Comments
 
LVL 76

Accepted Solution

by:
GrahamSkan earned 500 total points
ID: 17900520
Are you using MSComm control?

There is a settings property

    ' Use COM1.
     MSComm1.CommPort = 1
     ' 9600 baud, no parity, 8 data, and 1 stop bit.
     MSComm1.Settings = "9600,N,8,1"
0
 

Author Comment

by:jackjohnson44
ID: 17900695
I am using those settings.

Check the control panel setting to see what I am talking about.
0
 
LVL 76

Expert Comment

by:GrahamSkan
ID: 17900820
What sort of flow control are you using? How are you servicing the VB buffers? Are you getting problems on both send and receive?
0
Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

 

Author Comment

by:jackjohnson44
ID: 17900945
The problem only happens after running it a few hundred times.

I am not getting errors, I ask it a question and it gives me strange responses.

Either way, the setting seems to work.

Any idea how to change this setting programmatically?
0
 
LVL 76

Expert Comment

by:GrahamSkan
ID: 17901091
Sorry, No. I guess that you might be able to use use a driver API, but I'm not into it.

This may help you to get an overview.

http://www.wd-3.com/archive/SerialAttachedDevices.htm
0
 
LVL 26

Expert Comment

by:EDDYKT
ID: 17913698
The data may not come back in one shot. You need to read all data to determine whether the data is received

Show us your MSComm1_OnComm() routine
0
 

Author Comment

by:jackjohnson44
ID: 17914422
I am specifically asking how to programmatically set the slider that I mention above.

Please do not give alternatives, it is too late to change code.
0
 
LVL 26

Expert Comment

by:EDDYKT
ID: 17914483
I think the problem lies on your MSComm1_OnComm() routine. When you increase to highest performance means you will get all data back in one shot. Which implies you do not handle received data correctly
0
 

Author Comment

by:jackjohnson44
ID: 17914529
That is not the problem, the problem seems to be that my computer is not sending the commands exactly when I want, I think it might save them up sometimes.  If I send one command, I might have to wait to send the next.  I think they are both being sent really close together and my wait is being ignored. The machine I talk to gets confised.  Reguardless of the problem, the way I got around it was playing with this setting.  It has already been tested and agreed upon.  Instead of putting it in the release notes, I want to set it myself.  This is the only thing I am interested in.  Thanks for your help, but I am only looking to change this setting.
0

Featured Post

Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

When trying to find the cause of a problem in VBA or VB6 it's often valuable to know what procedures were executed prior to the error. You can use the Call Stack for that but it is often inadequate because it may show procedures you aren't intereste…
Most everyone who has done any programming in VB6 knows that you can do something in code like Debug.Print MyVar and that when the program runs from the IDE, the value of MyVar will be displayed in the Immediate Window. Less well known is Debug.Asse…
Get people started with the process of using Access VBA to control Excel using automation, Microsoft Access can control other applications. An example is the ability to programmatically talk to Excel. Using automation, an Access application can laun…
Get people started with the utilization of class modules. Class modules can be a powerful tool in Microsoft Access. They allow you to create self-contained objects that encapsulate functionality. They can easily hide the complexity of a process from…

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question