Re: Ports again, this time not network but COM ... (Prolific)

Dave AA6YQ

+ AA6YQ comments below

Another thread about ports, but not the TCP/IP kind, the COM port kind
-- the Windows name for serial ports. Specifically, the fake kind created by a USB port's driver.

+ COM ports created by a device driver are real, they just don’t exchange data with a physical serial port.

I have two eBayed "CI-V" cables for my Icoms. They have a USB A connector on one end and a 3.5-mm TS plug on the other. The chip in it talks USB to the computer converts the data to RS-232 signals then spits out TTL-level messages to the Icoms.

I did not pay attention when I bought them and they turned out to use the hated-by-all-hobbyists Prolific chipset. Vendor did not say this but I never asked, either, so hardly their fault. I had Zero problems with these from purchase in 2017 until last Fall when a Windows update made them behave strangely. They eventually worked OK, but only after an unplug/plug cycle once I had Commander running. Yes, I checked the power settings, etc, and they were correct as they had been before this started.

I put up with it for a long while and finally realized I should look to see if there was an updated driver. Looking in the Windows Update log, I noted that the Prolific driver had been updated (to back in September which sounded about right. I am uncertain whether Windows Update installed this driver or if I told it to. I'd love to blame Windows 10 but given that there is also a WSL update from the same date, likely it was me. Anyway, another Prolific update
( showed up in "View Optional Updates" in the last week or so and I clicked it. This seems to have corrected the apparent partial invisibility problem. I *know* I told Windows Update to apply this driver but oddly, it doesn't show up in the Windows Update log. I did update from W10-2004 to 20H2 between the two driver updates and that may be why the latter update doesn't show up.

The article below has an image showing the "View Optional Updates"
item in Windows Update.

This update did seem to fix things and now the ports are where Commander expects them to be when I start DXLab.

+ A problem with Prolific devices is that there are many counterfeit versions floating around, some of which don't work correctly.

+ Information about updating Device Drivers for USB-to-Serial-Port Adapters is here:


Dave, AA6YQ

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