How to send serial data (non printable char) with MSComm

[pancy]

I've been sticking to it for a long time already...I tried to send something using MSComm1.Output but when I send an integer valued larger than 127, my microprocessor (which is the receiving side) gets a zero. Here's my code:
...
MSComm1.Output = chr(0) & stringA & chr(integerA) & "."

my data format is like this:
a null (=chr(0)), then a string of two characters, then an integer of 1 byte (0 to 255), then a dot to denote the end of transmission

it works when integerA is 0-127 but fails when I send a value larger than 127

Could anypone please help? Does it relate to the inputmode Setting of the Com Port? I used
default Inputmode

any help would be great! Thanks alot.
Pancy

 

[neilharris]

It sounds very much like your microprocessor does not like characters over 127.
Try connecting to a comm port on a pc and see if it comes through correctly.

 

[pancy]

neilharris
I tried downloading some dll for the VB which allows me to send serial data, and it worked. So I think my microprocessor should have no prob.
However, I cant use that dll coz it only support sending but not receiving.
Any suggestion? Thank you very much!
Pancy

 

[JohnYingling]

You need InputMode = 1 ' Binary data and read the data nto a byte array.

http://www.VBResizer.com

Forms/Controls Resizing/Tabbing

http://www.VBCompare.com

Compare Code

http://www.VBSortGen.com

Generate Sort Class in VB

http://www.Vbcompare.com/Check.Htm(1979

Check To MS)

 

[JohnYingling]

Oops. For output of data..
"The Output property can transmit text data or binary data. To send text data using the Output property, you must specify a Variant that contains a string. To send binary data, you must pass a Variant which contains a byte array to the Output property."

http://www.VBResizer.com

Forms/Controls Resizing/Tabbing

http://www.VBCompare.com

Compare Code

http://www.VBSortGen.com

Generate Sort Class in VB

http://www.Vbcompare.com/Check.Htm(1979

Check To MS)

 

[johnwm]

I suppose you've checked that your protocol is 8,n,1 not 7,n,1

________________________________________________________________
If you want to get the best response to a question, please check out FAQ222-2244 first

'If we're supposed to work in Hex, why have we only got A fingers?'

 

[pancy]

Dear all,
In fact, I want to send a command to a robot. The command is typed in text1.text
part of my code is like this:

------------------------------------------------------
Private Sub Text1_KeyPress(keyascii As Integer)
Dim clcom As String, clname As String, clint As Byte, clcode As Integer

If keyascii = vbKeyReturn And Text1.Text <> "" Then
clcom = Text1.Text
clname = UCase(Left(clcom, 2))
clint = Mid(clcom, 3, 3)
Text2.Text = Text2.Text + clname & clint & vbCrLf
MSComm1.Output = Chr$(0) & clname & Chr$(clint) & "."
End If
End Sub
----------------------------------------------------------
so, when I type "FD100" the program will send out
0 "FD" 64 "." (64 is the hex of 100) through the com port

Settings of the MSComm are :
---------------------------------------------------------
MSComm1.RThreshold = 1
MSComm1.InputLen = 0
MSComm1.Settings = "9600,N,8,1"
MSComm1.commPort = 1
MSComm1.PortOpen = True
MSComm1.SThreshold = 0
---------------------------------------------------------
The problem is when I type "FD200", (in fact it's any number 129~254), I got zero at the other end.
I tried using some downloaded dll and it worked. but I couldnt use this dll in my project.
I tried the variable type of clint as byte, string, integer, variant...all dont work!

I really have no idea...
Please kindly give me some idea you can think of. Thanks alot!