Concatenating individual incoming bytes into a string on a static text box.

Hi, I am trying to concatenate incoming bytes from a comport so that they appear in a static textbox in my GUI. I have also tried to set it up so that when there is a character return, the data will move to the next line and continue concatenating. I have pasted the code below. Right now I have it so that the individual bytes will appear, however they won't append each other, and the incoming byte will replace the previous byte.

function rxbyte_Callback(hObject, eventdata, thisfig)
  handles = guidata(thisfig);
% pingport = getappdata(handles.main_window,'port_handle');
% bytes=fread(pingport,pingport.BytesAvailable);
bytes=(fread(hObject,hObject.BytesAvailable));
class(bytes)
hello=(get(handles.Incoming))
class(hello.String)
variable=[strcat(hello.String,char(bytes))]
hello
variable=['']
if(bytes==13)
variable =[''; variable];
set(handles.Incoming,'String',strcat(variable))
else
    variable=[variable char(bytes)]
    set(handles.Incoming,'String',strcat(variable))
end
strcat(handles.Incoming,'String',variable)
set(handles.Incoming,'String',variable);

Thanks,

Malik

Answer 1

[Walter Roberson]

One thing that occurs to me immediately is that multiple bytes might be read with the fread(), but your "if" is testing as if only a single byte had been read.

Oh yes, and you are initializing "variable" to '' each time rather than starting with whatever was already in the uicontrol.