On Nov 25, 11:21*pm, (Roy Badami) wrote:

Mizter T wrote:

My guess is that it is just a single bit on the Oyster card, so one
size must indeed fit all. *Or actually two sizes, namely auto top-up
enabled, or auto top-up disabled.

Well, auto top-up by £20, or auto top-up by £40.

Yeah, I realised that after I posted. *So there are three states (off,
20 quid or 40 quid). *If we assume there must therefore be at least
two bits coding the state, that means that it would be possible to
support at least four states.


Random bonanza - top up with an annual all-zones Travelcard whenever
it runs out?