We have the MD-HMI that can be connected to the T100MD+ PLC expansion port. This is the easiest and lowest cost solution.
In the samples folder of TRiLOGI version 5 we also have a demo program that showcase how to program a matrix keypad connected to the PLC. But it is a messy job to connect a matrix keypad and it also uses quite a lot of the digital inputs and outputs on the PLC to implement matrix keypad compared to using MD-HMI.
Another alternative is to use serial port based HMI. See descriptions of user interface options at:
http://www.tri-plc.com/dataentry.htmNote: There is no Keypad option for H-series or E10+ PLCs.