Upvote:2

Aprove answer 
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:[NSURL URLWithString:timetable_URL]
                          cachePolicy: NSURLRequestReloadIgnoringLocalCacheData
                        timeoutInterval:30.0];
NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];

Upvote:1 

- (NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse
{
   return nil;
}

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