viewing changing amounts

6.11: adde/mem display:
. the system should be showing
how much mem it's using;
but, if the mem is changing rapidly,
then then display will be unreadable:
in that case,
the minimal display has both the amount,
and the rate of change;
so, then if you see the rate of change
is non-zero
then you know the amount will change soon,
it is only frozen temporarily for readability .