If you search the forums you will see some references to difficulties in using serial to USB adaptors on a PC or laptop. Issues are described where Windows treats the adaptor as if it were a mouse, comm port conflicts, baud rate errors and so on.
I searched for a suitably qualified company that would use drivers that the ‘experts’ say are reliable and eventually bought two serial to USB adaptors from Easysync .
I can report that the products have worked flawlessly on my laptop (Win XP) and I have had no comms issues at all.
Of course it is still advisable to keep a shortcut on the desktop that takes you straight to the ‘System’ settings of Control Panel – because software you use will reconfigure your nicely configured virtual comm ports when you least suspect it …but it is obvious when that happens and easy to put right – this is not the fault of the adaptors.
The main points to note are:
1 – these adaptors work
2 – the virtual comm port drivers are from FTDI and they work
3 – there is a generous FIFO buffer of 128 / 384 bytes
4 – They have xmit/rcv lights so you can see whats going on!
The following is taken from the suppliers web site..
* FIFO: 128 byte transmit buffer 384 byte receive buffer
* Enhanced RS232 transciever gives serial port speed of up to 500K bps – this is faster than most and will help to avoid any further speed issues.
* Adds one RS-232 serial port by connecting to USB port
* Installed as standard Windows COM port
* Works with USB 1.1 & 2.0 host port
* One DB9 male connector
* Serial Communication Parameters
-Parity: None, Even, Odd
-Data bits: 7, 8
-Flow control: RTS/CTS , DSR/DTR, X-ON/ X-OFF, None
* RxD, TxD LEDs for monitoring port status & easy diagnostics
* integral 1m USB cable with moulded strain relief
* Quality 4-layer pcb design
* COM Port Number can be changed to COM1 to COM4 to support HyperTerminal, or any other COM port number required
* Industry Standard FTDI chip set & drivers for maximum compatibility
* Supports Windows XP, 2003, 2000, ME, 98, Linux, MAC-OS8,9,X
* Full RS-232 modem control signals
* RS-232 data signals: TxD, RxD, RTS, CTS, DSR, DTR, DCD, RI, GND
* Powered by USB port. No external power adapter required.