vb com port settings

Posted on 2006-11-08
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?
Question by:jackjohnson44
  • 4
  • 3
  • 2
LVL 76

Accepted Solution

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"

Author Comment

ID: 17900695
I am using those settings.

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

Expert Comment

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?

Author Comment

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?
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

LVL 76

Expert Comment

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.
LVL 26

Expert Comment

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

Author Comment

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.
LVL 26

Expert Comment

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

Author Comment

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.

Featured Post

Free Trending Threat Insights Every Day

Enhance your security with threat intelligence from the web. Get trending threat insights on hackers, exploits, and suspicious IP addresses delivered to your inbox with our free Cyber Daily.

Join & Write a Comment

Article by: Martin
Here are a few simple, working, games that you can use as-is or as the basis for your own games. Tic-Tac-Toe This is one of the simplest of all games.   The game allows for a choice of who goes first and keeps track of the number of wins for…
Enums (shorthand for ‘enumerations’) are not often used by programmers but they can be quite valuable when they are.  What are they? An Enum is just a type of variable like a string or an Integer, but in this case one that you create that contains…
Get people started with the process of using Access VBA to control Outlook using automation, Microsoft Access can control other applications. An example is the ability to programmatically talk to Microsoft Outlook. Using automation, an Access applic…
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…

743 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

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now