wrote
But that delay is only on the bendis, and not all of them that are equpped
with iBus. Double deckers with operating iBus do not have a delay when the
button is pressed.

That's quite right - it's an ibus/bendy thang.

Drivers get an audio and a visual signal when somebody rings the bell.
They will receive a regular signal, just a beep, if regular passengers on
the lower level push the button. But they see/hear that signal only once,
to avoid being annoyed, as passengers can continue ringing to their
hearts' delight. They also receive a different one-time signal, which is
more like a whistle, to let them know if somebody from the upper deck is
ringing.
The blue button for disabled customers is more like a small siren or a
very loud beep.

Thanks for that.


--
Andrew


If you stand up and be counted,
From time to time you may get yourself knocked down.
But remember this:
A man flattened by an opponent can get up again.
A man flattened by conformity stays down for good.
- Thomas J. Watson Jr.