Error message not connected

Hellow, im working with two motors for a project and they are connected via the Control instrument toolbox. Now i have used it in my gui, so the motor connect before the figure is shown. So in the function density_CreateFcn. But know, there must be a fault message when the gui starts and the motors arent connected properly. Anyone who has experience with this? Thx in advance

Answer 1

[Matt Fig]

t = serial(...)  % Try to open the connections.
u = serial(...)

try
   fopen(...)
catch
   errordlg('First Motor not connected properly.', 'Connect Error');
end

try
   fopen(...)
catch
   errordlg('Second Motor not connected properly.', 'Connect Error');
end

Now you should put a pushbutton on the GUI which has the same above code in the callback. Perhaps one pushbutton for each motor.

[Walter Roberson]

The serial port version of fopen() has no outputs: if there is a problem it throws an error.

[Matt Fig]

Oh yeah, oops... Long day...

Answer 2

[Sean de Wolski]

If the motor isn't connected it will error when it tries to connect to it because it won't be able to.

Post the full error message text for a more pinpointed response.

Answer 3

[Walter Roberson]

I suspect that the answer you are looking for is that you should use a "try/catch" block around the fopen() for each of the motors. Though depending how you are finding the device information for the motors, you might be able to partly detect the condition earlier (e.g., if you only detect one COM port then you know that you don't have two motors connected.)

Answer 4

[Fiboehh]

The motors are connected like this:

t = serial('COM1','BaudRate',57600,'DataBits',8,'Stopbits',1,'ErrorFcn','Fout opgetreden!','Parity','none','FlowControl','none'); % rotations- motor
u = serial('COM3','BaudRate',112500,'DataBits',8,'Stopbits',1,'ErrorFcn','Fout opgetreden!','Parity','none','FlowControl','none'); % microcontroller
fopen(t)
fopen(u)

Now i want a message box that gives a error : 'Serial connection not established, please check connections and try again.' And a button to try if the new connection works. Maybe a try/catch is good, but i dont now how to make the error box for the gui.

[Walter Roberson]

The specific error for serial() failing to create the internal java object is MATLAB:serial:serial:cannotCreate

The specific error for serial fopen failing to open the internal java object is MATLAB:serial:fopen:opfailed

You can create an error dialog with

ed = errordlg({'Serial connection not established.', 'Please check connections and try again'});

uiwait(ed);