3
The Drivers for Windows
Figure 13: Advanced port options
3.3.1 Rename the Serial Port
The option “COM Port Number” on top of the advanced settings allows to rename the port. You
may select any free port number. It is Windows which refuses a change, if the new port name is
already occupied.
3.3.2 Miscellaneous Options
In the lower right corner of the Advance Options (figure
13
) are some seldom changed options.
3.3.2.1 Enable faster Responses
In the middle of the left part is the section named “BM Op-
tions”. The parameter “Latency Timer” can be reduced to 1 millisecond, if there are problems with
certain applications. The default value is 16, to reduce the USB protocol overhead and bandwidth
usage. Usually the serial port buffers incoming data for up to 16 ms, or until 62 bytes of data
are received. When either of the criteria becomes true, the data is sent to the Host PC. Then the
application software will recognize the received data. If a small amount of data is received, or the
June 2009
USB-COM PRO User Manual
16