Quatech RS-232 - Manual (Page 21)

Figure 8--- Windows Device Manager
6. The ESC(LP)-100 serial ports are also listed under the group Ports
(COM and LPT). Windows 95 does not assign COM1-COM4 to
ports addressed at nonstandard locations. The ESC(LP)-100 ports
will be enumerated starting with COM5 (or higher) even if lower
logical numbers are available.
7. Select any of the Quatech Serial Ports listed under the group Port
(COM and LPT) and click the "Properties" button. This action
opens a properties dialog for the specific COM port on the
ESC(LP)-100.
8. Click the "Port Settings" tab and then click the "Advanced" button.
The ESC(LP)-100 driver will display a custom Advanced Port
Settings control, which allows the ports UART compatibility mode
and FIFO threshold levels to be configured. The threshold values of
full-scale for the transmit buffer and ¾ -scale for the receive buffer
shown below are optimal for most applications. Note that the FIFO
option for each of the ESC(LP)-100's eight ports is configured
independently.
ESC(LP)-100 User's Manual 15