The LSNS is in deserialization mode, it writes a life value to the particles it touches. Since the read distance of an LDTC is set with its life property, you can use a deserializing LSNS to control the read distance of an LDTC in-game. So instead of mounting an LDTC to a piston and moving the piston a distance we just tell the LDTC at what distance it should read. How this works exactly is explained in the Serialization based FILT ROM save above.
Well, we set LSNS tmp property to 3 for deserialization, and we'd set tmp to 1 if we wanted serialization.
For instance we can measure a temperature, turn it into a number, move that number to the other side of our save and turn it into the exact same temperature again.
For our ROM we just use deserialization, we turn binary addresses (numbers) stored in FILT into life values to control the read distance of an LDTC. If we deserialize a binary number of 5 for example that would tell our LDTC to read a particle at 5 pixels distance from the LDTC. So the workflow goes like this:
Set ROM address to read in a FILT -> LSNS reads FILT value and turns it into a life value -> LDTC gets the life value and uses it as the read distance.
That's actually a very genius way to make a writer!