The systems used abroad (and also on Megatrain) are far simpler.
On Megatrain you simply present the code (printed, hand written or on a device) to the guard who has a printed list of codes and names to cross-reference.
On the DB» /OBB EuroCity service and also on Trenitalia, the guard has a PDA or smartphone into which they type the ticket's code (or scan the barcode if you've printed the ticket).
With both these systems, you don't need a printer or expensive phone, just a pen and paper to write down the code.
The 'simple code' scheme only works for a ticket that is valid on one specific booked train, like an Advance. Once you get into tickets that are valid all day, or all month in the case of an anytime return you need something much more bullet proof to prevent repeated re-use.
Paul