SerialPort Error HifiModule

LunaS

Hi,
I am having an issue with the BPod Hifi Module. I can only run my script once, then I always get the following error:

Error using serialport
Unable to connect to the serialport device at port 'COM8'. Verify that a device is connected to the port, the port is not in use, and all serialport input
arguments and parameter values are supported by the device.
See related documentation for troubleshooting steps.

Error in ArCOMObject_Bpod (line 204)
obj.Port = serialport(portString, baudRate);

Error in BpodHiFi (line 88)
obj.Port = ArCOMObject_Bpod(portString, [], [], [], 1000000, 1000000);

Error in TestPhase1_LearningTask_HiFi (line 17)
H = BpodHiFi(BpodSystem.ModuleUSB.HiFi1); % The argument is the name of the HiFi module's USB serial port (e.g. COM3)

Error in run (line 91)
evalin('caller', strcat(script, ';'));

Error in LaunchManager>launch_protocol (line 843)
run(protocolPath);

Error while evaluating DestroyedObject Callback.

If I re-start Matlab I do not have this issue anymore. But for now I need to re-start Matlab every time I want to start a new protocol/ run a new session, which is not ideal.

Do you maybe know why that is the case?
Thanks in advance for any help!
Luna

Josh

Hello Luna,

Can you please share the line of your protocol where you initialize the HiFi module?

If you initialize the module with H = BpodHiFi('COM3') you need to make sure that H is cleared from all workspaces in order to create a new instance of H. If you made H global, you'd need to use:
clear global H

-Josh

LunaS

Hey Josh,

thank you for the quick reply. I used
BpodSystem.assertModule('HiFi', 1); % The second argument (1) indicates that the HiFi module must be paired with its USB serial port
% Create an instance of the HiFi module
H = BpodHiFi(BpodSystem.ModuleUSB.HiFi1); % The argument is the name of the HiFi module's USB serial port (e.g. COM3)
My error occurs because I use global BpodSystem H instead of global BpodSystem to be able to use a softcode function to stop a sound from playing when the animal is leaving a noseport too early.

sma = AddState(sma, 'Name', 'SoundMatlab', ...
'Timer', S.GUI.SoundDuration, ...
'StateChangeConditions', {'Port2Out', 'StopSound', 'Tup', 'WaitForResponse'}, ...
'OutputActions', OutputActionArgument);

sma = AddState(sma, 'Name', 'StopSound', ...
    'Timer', 0, ...
    'StateChangeConditions', {'Tup', 'EarlyWithdrawal'}, ...
    'OutputActions', {'SoftCode', 1});

function SoftCodeHandler_StopSound(softCode)
global H
if softCode == 1
if isa(H, 'BpodHiFi')
H.stop();
disp('Sound stopped by SoftCode 1');
else
disp('H is not an instance of BpodHiFi. Unable to stop sound.');
end
end
end

Maybe there is a different way to stop the sound early but I haven' figured it out yet. Do you maybe have a suggestion?

Thanks,
Luna

Josh

Hello Luna,

You shouldn't make H global if at all possible.
To stop the sound on entering a state, use:
{'HiFi1', 'X'} in your output actions.
Other commands are given here.

Please let me know if this works for you.

Thanks,
Josh

LunaS

Hey Josh,

thank you! It works like this now.

Best,
Luna