Well the prolific chip set has had issues I know. Jerry has stated the correct chip set to use is the FTDI. My guess is the programming if the pin on the prolific didn’t work. Try to get a cable with the Ftdi and see what you can accomplish.
The hobby is indeed one full of nooks and crannies. And it can sure suck down some money.
I bought the DTECH 10 ft usb to serial ftdi cable from Amazon. I don’t use the asiair so can’t say how it might work with that. It works like a charm in myPMC8 with windows.
If you are using windows you can download an ftdi driver from parallax web site. See if that driver recognizes your usb to serial. It won’t if it’s a prolific.
Wes, Southport NC
EXos2-GT PMC-8, iExos 100
ES ED 127, 10" LX200GPS+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired