John, It's the felHR85 UsbSerial library. That the base library that is then wrapped into a B4A library. It supports several different USB devices. Some with more support than others. Link Kurt
On Friday, February 12, 2016 8:54 AM, John R. Hogerhuis <jho...@pobox.com> wrote: On Friday, February 12, 2016, Kurt McCullum <kurt.mccul...@att.net> wrote: John, The drivers are built into the library I am using. It supports an Android OS as old as 3.1. Kurt Interesting. What library are you using? -- John.