Identifiers must be chosen with utmost care when BasicCAN is used in order to keep the window of the filter as small as possible. All messages that are passed by the filter must be read and checked by the microcontroller. This means that the final filtering is done in software. A BasicCAN controller has no support for automatically answering Remote Frames. Instead, the application must handle them. This puts extra load on the host microcontroller or processor, but ensures that the value returned gets updated. If a message is received when both receive buffers are full, the oldest messages are kept. Thus, newer messages might be lost if the host microcontroller does not read the messages fast enough.