Serial communication-MSComm control in VC++

Posted on 2000-03-14
Last Modified: 2013-11-20
I am using MSComm control in VC++. I could write a data into the port . But according to my project 5 bytes should arrive to PC. but when i say
it is returning a bstr which contains only one byte of data of length 1. But the same is perfectly working in VB. I could'nt trace out where is the problem.
Question by:karthik1979
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Expert Comment

ID: 2618733
Does the data contain embedded null characters ('\0')? The mscomm class does not handle those; instead it terminates the string returned there.

Author Comment

ID: 2620393
out of 5 bytes 1 and 5th byte are same .they resemble a special character which appear as letter I in bold

Accepted Solution

orozco earned 100 total points
ID: 2878602

You have to declare your a variable as the following:

int CControlComView::ReadCharacter(_bstr_t *a)
  *a = m_MSComm1.GetInput();
  return a->length();

you don't have to declare "a" as a variant.

good luck.

Expert Comment

ID: 3771279

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