AMX Modero NXD-500i Operation/Reference Manual page 152

Appendix B - Complex Script Support
Some languages, notably Hindi and Tamil, are not supported by coded pages. These languages will display
"???" for characters entered via the language bar, even if the selected font supports the language.
Text in these languages can still be pasted via the clipboard or via the Alt-<Scan Code> method.
For more information on TPDesign4 and its complex script support, please refer to
the TPDesign4 (v3.0 or higher) Operation Reference Guide, available at
www.amx.com.
140 NXD-500i 5" Wall/Flush Mount Touch Panel with Intercom