What is the purpose of the external data card?
The external data card stores settings for transfer to other controllers and devices; it can also be used to put fresh settings on a controller. The card is read on start-up (a file called deployment.sqllite3), if this file is not present the controller will create a new version from the currently applied settings.
What data card types are supported in the RSC-HMU Controller?
The controller supports only certain data card types. From testing it has been confirmed that only MicroSD HC cards of 4GB or less and of class 4 or 6 seem to be supported.
To test if your card is supported, insert the blank card in the controller and cycle the power. If the controller can use the card, it will write a new file called deployment.sqlite3 to it; if the file is not written, the card is not usable in the RSC-HMU controller.