GUI send available com ports to popup menu

Hi, i want to chk all available com ports and make them visible to select in a popup menu. to find the ports I assume i need to use instrhwinfo('serial') in my code:

list = instrhwinfo('serial');
for i=1:length(list.SerialPorts)
    ports{i} = list.SerialPorts(i);
end
set(handles.com_number,'string',ports);

where com_number is the tag of the popup menu but the list in the popup menu is empty what am i doing wrong?

[Geoff Hayes]

d - where is the above code being called from? Is it within the _OpeningFcn of your GUI or within a callback? Please copy and paste the full function signature and body so that we can get an idea of how and where the code is being used.

Also, have you put a breakpoint at the line where list is initialized to make sure that there is at least one serial port? Is ports being populated?

[Daniel]

you both helped me a lot. you made me notice that i wrote it in the wrong place (not the openngFcn) and Walter directed me to an example. its working now. so thanks to you both

Answer 1

[Walter Roberson]

http://www.mathworks.com/matlabcentral/fileexchange/26371-simple-gui-for-serial-port-communication