Single-byte key addressing (for boards with fewer than 256 keys)

[noseglasses]

@noseglasses

There is no extra overhead. The class could have (inline) getters and setters for row and column values, which would encapsule the bit manipulations. You probably couldn’t distinguish both implementations in the assembly code.

See also

Do accessors increase PROGMEM consumption?

There were discussions about the benefits of accessor functions [1], [2], [3]. Apart from religious aspects of the discussion, the statement that accessors cause runtime costs appeared quite often. This is something that is hard to get out of the heads of programmers coming from other languages that do not feature function inlining, C programmers included. But C++ has its own rules. Inline functions can actually disappear from the assembly and thus from our precious PROGMEM. C++'s inline keywo…