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is being updated, drivers are kept updated, too.
Another way how to update drivers in Windows 7 is very
complicated or rather impossible.
2.2.2 Windows XP
Windows XP drivers are stable for a long time, thus there
is usually no reason for update them with the exception
that another software application using FTDI IC on the
same PC requires it. In that case, drivers are available for
download at
2.3
Troubleshooting and
Special Requirements
Some of applications have special requirements for
RS-232 communication, which demand particular correct
settings of the UCAB232 converter.
If there is any difficulty in communication between the
RS-232 connected device and PC try options listed below.
Red LED indicates transmitting, it can serve as a check on
that software application sends data to a correct PC port.
In other case, please check the COM port number in
software application and the assigned COM port number
by operating system.
The COM port number can be found and/or changed in
Control Panel/Device Manager/Ports.
If the RS-232 connected device does not reply (LED
indicator does not blink) although software application
sends data, it is possible that there is not correctly set
„Baud rate“ (communication speed), „Data bits“, „Parity“,
„Stop bits“ or „Flow control“. Please check that the
settings meets specification of the RS-232 connected
device.
2.3.1 High demands on
time response
If the connected device replies (LED indicator blinks) but
software application still does not receive data it is
possible that the software application has high demands
on time response.
The way of communication through USB is very different
than communication through RS-232. USB uses packets
of 64 B size. Furthermore, a RS-232 device device can
receive only on PC request. Hence it is almost impossible
to assure time response lower than about 1 ms.
Time response settings can be done in Control Panel/
Device/Manager/Ports/.../Port Settings/ /Latency Timer. In
case of troubles set this number to 1 ms.
Fig.4: COM port Enhanced Settings
