I bought a Device license for KNX. Can I use it to control Modbus too?

No, you can't. Buying a license for one of iRidium products you can control only the driver you indicated when purchasing the license (in this case - KNX). All other drivers cannot be controlled with the same license.

To receive the license which enables control both KNX and Modbus from one control panel you need to purchase activation keys for each of these products and activate them for one panel (using the same HWID). The license file created after activation of the second key will contain two supported drivers.
The second way is to purchase Full license which includes all iRidium drivers (besides HDL-BUS Pro).

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