SX-Key and USB to serial converter

glenn jones

My laptop doesn't have a built-in serial port. So I went and bought a belkin USB to serial conversion cable/dongle. Technically it is meant for attaching PDA serial cradles to laptops but says it supports any serial device.

It is acting rather flaky. I can do a program or a read with it but only once and then it says it can't find the Sx-Key on COM4 (or COM2 tried both settings). If I unplug the adapter from the USB port and plug it back in, I am good for one more operation then back to it can't find the the Sx-Key.

Run or Debug don't seem to work at all.

I have tried v 2.02 and v3.0 of the SX-Key software

Any thoughts?··

Glenn

Ken Gracey

Glenn,

You'll get a lively set of responses on this request. I'd venture to say that the Belkin adapter is not fully RS-232 compatible, or at least it doesn't work with our products like the FTDI adapter does. I wish I could help you specifically with the Belkin unit since that is what you have. But I believe your best chance of success lies with the FTDI USB to Serial adapter. The FTDI adapters are Windows approved, too.

There was one setting in the Ports=>USB>Advanced properties that made even the FTDI adapter work more reliably - the "latency timer". If you set it as low as it will go this might change the flakiness problem. I also wonder if you're using the latest drivers from Belkin.

Ken Gracey
Parallax, Inc.

glenn jones

Hi Ken,

I couldn't find the ref to Ports=>USB->Advanced (on WinXP) but I did get updated drivers from Belkin, thanks for the reminder. Prior to buying the belkin, I was trying to use a different USB hub (with a built-in serial and parallel conversion) as well .. so I backed off those changes too (via system restore - that also put me back to SX-Key 2.02 which works as well).

Seems to be working ok with SX-Key (and XGS) now.

Thanks for your help.