Mike, the first Firmware for the TIU to support the Wifi module was version 5.0. This version only has limited functionality and is no longer supported as the app version required for it to work is no longer available for download. The latest version of the TIU firmware is 6.1 which fully supports the WIU (WiFi Module). The WIU itself also has firmware revision which is currently at release 1.1 and requires the latest version of the app from the app store to work properly. And as always upgrade your DCS remote to match the same version of the Firmware that is running on your TIU.
All hardware revisions of the TIU are compatible with the the WIU. The REV. L TIU does have a USB (type B) port that allows the WIU to plug directly into the TIU via a USB cable. All older revisions of the TIU will require an inexpensive USB to Serial (DB9) adapter to allow the the WIU to connect to the TIU.
All TIUs use the same software/Firmware and there are no limitations to using the latest TIU firmware between any of the TIU hardware revisions.
