VB Help

[cncmachineguy]

Oh thank you rmteo! I had just found the timer, but didn't get the interval part. That works awesome!!

Ok, now to convert those 2's complimented numbers to show negative values instead of 65533 and such.

[gadelhas]

Hi cncmachineguy;

To receive data from the serial port you should always use SerialPort Event Trigger like the one i posted.

Private Sub DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
        Dim recepcao As String
 
        recepcao = SerialPort1.ReadExisting
 
        If recepcao = "%TE" Then
            GetCursorPos(rect)
            SetCursorPos(rect.X - 1, rect.Y)
        End IF
End Sub

Don't use timers to poll the serial port, it is not very efficient!!

If you want to send data to PIC, like a press of a button, then you can use the timer. just put the code that you have inside the button, inside of the timer, and choose the interval!

I wrote this post in a little hurry, later i have more time and i came back here!

[cncmachineguy]

Thanks gadelhas, point taken. Right now the pic is not allowed to send data unless asked for it. The pic side code is modified from the CDC for dummies thread. This part is working great. Thanks to all of you.

Now for the next part (this seems like it should be easy, but of course not). The 18 bytes sent from the pic represent 9 words. From here on, I will just refer to 1 word. The rest will be the same action.
Let's call them data(0) and data(1). To put them together I did this:

detain =(data(0)*256)+data(1))

this works fine with 1 problem. It is really a signed number, so 65533 should read -2.
I have tried all sort of ways to get here, but continue to fail. I am sure it has to do with dim as or the way I am putting the word back together, but I am at a loss.

Anyone know how?

[gadelhas]

What do you receive from PIC, and what do you want to do, can you give me a full example, its just because english is not my native language, and perhaps i'm not understand something

[cncmachineguy]

From PIC:
data(0) and data(1). these 2 bytes are the highbyte and lowbyte of a word. -32768-32767

I need to see the word like that. for example the word may equal 3, or it may be -3. right now I will see 3 or 65533.

So how to put the bytes back together and show signed integer?

[mister_e]

I never had any purpose to justify the use of signed<->unsigned conversion myself, but you may have a look at
http://support.microsoft.com/kb/189323

It's all about how you interpret/display the numbers... like Floating point in PBP... or show decimal on a LCD

[cncmachineguy]

I would normally side with you steve, but on this one I am having issues. The numbers bounce around zero, so I get to watch 3,3,4,2,1,65533,65534,4,1,.....

Seems like it would be better to have the numbers more right

[gadelhas]

From PIC:
data(0) and data(1). these 2 bytes are the highbyte and lowbyte of a word. -32768-32767

I need to see the word like that. for example the word may equal 3, or it may be -3. right now I will see 3 or 65533.

So how to put the bytes back together and show signed integer?

IN VB.Net, signed bytes are Sbyte and signed Words are Short

Exemple;
Dim data0 as Short=-32500
Dim data1 as SByte = -65

But if the PIC is sending the 65533, the PC will see 65533 and not -3. Don't know if can help you.

[cncmachineguy]

Ok, different question. How do I put 2 received bytes back together to make 1 word?

[gadelhas]

Ok, different question. How do I put 2 received bytes back together to make 1 word?

Tell me one thing first, what is the type of you variable where you receive the data from PIC, Integer, String....

[mister_e]

Like you did have to be fine.
WordOut=(MSByte*256)+LSByte