Hi,
There are several adapters and cable adapters that work, but beware, some of the older ones (Some Prolific chip based) that do not have newer drivers for Windows ... and other OSes ...
I've had great success using the "Gearmo USB to Serial" cables ... many places sell them, the ones I bought were NOS on eBay ... I paid about $5each for three cables ... two are 1 USB to 4 RS-232, the third is 1 USB to 2 RS-232 ... Just plug'em in and go. Nothing fancy.
The only thing I can say is I think I tried 4 or 5 cables that didn't work before I tried the GearMo brand that just plugged in and worked.
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