jazz usb-to-serial converter

Hello, Just checking in what USB to serial converters you would recommend for connecting to Jazz. I have 2 Jazz processors here and I am unable to communicate with either of them. They are older models and only support serial via MJ20-PRG. I am using Unitronics serial cable p/n: MJ10-22-CS25. I get no errors in Device Manager when I plug in the USB-to-serial converter. It grabs Port 3. But if I set U90 ladder to Port 3, the communication still times out. I have several USB-to-Seri

You've stumbled into one of the mysteries of the computer world - USB converters not playing well with external microprocessor-based devices. I Googled "FTDI vs Prolific" and found all kinds of conflicting information, with fanboys on both sides. Sometimes FTDI works where Prolific doesn't, and vice versa. And then there is the issue of counterfeit chips, which adds another aspect of intermittent / non-functionality for both manufacturers. Many moons ago I tried several USB converters an