
224 The Circuit Designer’s Companion
(safely) until it reaches the JMP RESET, at which point it restarts.
The effectiveness of this technique depends on how much of the total possible
memory space is filled with NOPs, since the processor can be corrupted to a random
address. If the processor accesses an empty bus, its action will depend on the meaning
of the #FF
H
instruction. The relative cheapness of large ROMs and EPROMs means
that you could consider using these, and filling the entire memory map with ROM, even
if your program requirements are small.
6.5.3 Re-initialisation
As well as RAM data, you must remember to guard against corruption of the set-up ...