I see a lot of posts about communication[usb] errors and various problems with control reliabilty
My current controller is not SB,but like SB it is a high perf. USB system.
I have chased many inexplicable problems, spent days revising,checking wiring,grounding,encoder cables , most of them initially identefied as noise ,ground loops etc.
yesterday with a real expert,s help we systematically went thru EVERYTHING and found that my 5V power supply[not the computer supply,but a separate industrial grade was only outputting 4.05 - 4.2v .
I replaced it and get a solid 5.02. made a difference in
limits response,IO rates ,step pulse stability etc.
as I understand it USB devices designed for 5V "logic" only tolerate a 10% drop before their performance slips.
can't say it is always the problem but it sure solved.
my problems
Carl