Bob,

Here are the 3 different chip types in my USB-to-serial cable inventory.

Future Technology Devices International
[ 521.640253] usb 6-5: FTDI USB Serial Device converter now attached to ttyUSB0

Prolific Technology
[ 117.232417] usb 6-5: pl2303 converter now attached to ttyUSB0

Silicon Laboratories
[ 855.444230] usb 6-5: cp210x converter now attached to ttyUSB0

Jim KC9HI