- (IBAction)btnInvoke_clicked:(id)sender {
    [ctlActivityIndicator startAnimating];
    JetstreamServiceClient *client = [[JetstreamServiceClient alloc] initWithURL:CurrentSettings.JetstreamURL andAccessKey:CurrentSettings.AccessKey];
    [txtOutput setText:@""];

    GetPassesRequest *request = [[GetPassesRequest alloc] init];

    request.LogicalDeviceId = [txtLogicalDeviceId text];

    [client DeviceSpecificCommand:request];
}