HEDS5540 optical encoder

[richard]

But the precision is terrible, can you explain me the right way?

157/1440 = .109 mm per encoder tick

.109 * 256 * 10 = 279

distance * 10 = (counts * 279)/256

to use pbp's higest resolution integer functions

counter = enc_counter */ 279 

lcdout  Dec counter/10 ,".", dec counter//10     ; display counter value on LCD

problem here is that when enc_counter > 60000 [or thereabouts] the internal 32bit result will overflow and the result will be wrong
you could look at nbit math


ps you could also use div32

counter = enc_counter * 1000
counter =  div32 917

lcdout  Dec counter/10 ,".", dec counter//10     ; display counter value on LCD