A timeout is implemented to prevent reading from a serial device getting stuck when no data is available. The timeout is defined as the amount of time to wait between bytes being received.
SerialCom: Reading zero bytes is valid and does not return an error.TextSerialCom: Reading zero bytes before termination is reached throws an exception.On Linux, this is done using the VMIN/VTIME parameters. This means that the timeout setting is rounded to the nearest tenth of a second.
Also sneaking in a few updates to gpibscan. Cleans up the code by using TextSerialCom.