- it would be bufferred if the cost is low later if it brings flicker, but for now let's consider that it will be fast enough and if we can avoid buffering, we would
- official library takes 132% of the arduino uno memory so no way we use it; it is mainly due to the buffer which is 32x128 bytes
- the next step is to reverse-engineer it to keep no buffer and rely on a state according to our very own usage