Al 04/07/13 12:08, En/na Dennis Poon ha escrit: > thanks. > I am not using the fpc email as it seems off topic. > > May I know the exact brand and model number of the adapter you used?
I don't know the exact model, but it is one of these http://vscom.de/1_1_09.htm however there are other brands that should work equally well > I have an ATEN usb-to-serial cable (UC-232A) but I am not sure how to > connect its serial pins to rs-485 's DIFFERENTIAL LINES and how to set > that adapter into half-duplex translation mode. That's not good: you'll need a level converter (which will probably cost more than an usb to rs485 adapter) *and* use one of the control pin to commute between tx/rx, the problem is, when you transmit you don't know when the last bit exits the serial port, so you cannot reliably control the switching pin. An usb<->485 adapter usually does it all by itself at the right time. Bye -- Luca _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal