hey guys ok I bought a Chinese stand alone controller because I really want to get away from running my cnc control on the PC as I have with mach 3 so far, and a stand alone controller was really the way I wanted to go here for a lot of reasons. I wish I could afford to buy a real deal Fanuc controller but thats just not in the cards for me right now so I bought one of the many versions out there of the SZGH 990MDb Chinese controller despite the fact that there are almost no real examples out there of people actually successfully using these and very little info in general out there about actually setting up these things

the instructions, if you could even call them that, are pretty crappy Chinglish and barely decipherable but I have actually managed to get it all hooked up dialed in and calibrated and working perfect on my CNC router table. everything works as it should so far with one huge exception, when actually running a program the Z axis winds up becoming reversed...

now I know there are tons of threads out there with guys who have there configurations wrong and have reversed axis' but that is NOT the case here, when I use the handwheel everything is as it should be, moving the spindle down goes in the negative direction, MDI inputs all work exactly as they should, it's only when actually hitting cycle start and actually running a G code program that the Z acts completely flipped, Z positive moves become down and negative becomes up. once I end the program and exit running te code it reverts back to how it should normally work. I have went through every parameter and setting I can find and nothing solves this problem, I even tried a full system reset and even then with the bone stock factory configuration it is still the same. of course I can flip the Z axis in the parameters, but that just makes it work wrong all the time except when running a program, it already IS actually configured and working correctly right now, right up until the point I load some g code and hit cycle start

now I have already somewhat solved the issue by editing the post processor and adding a -1 to flip the output from the processor in the VAR Z_POSITION= line and I can now post out code and run and cut parts no problem, so really in a sense I have kinda already solved the problem, but this really is bugging me as to why?? has anyone seen any kind of controllers that would intensionally require a ...|-1] to flip the Z axis in the post processor like this? I have actually found only one other post processor out there of everyone I have looked at, and I have looked at a whole lot of processors, the only one I have found that inverts the Z normally in the PP like this is a Multicam classic mm post processor, so this has me thinking maybe this is not so completely unheard of or abnormal after all, and maybe as long as it is posting correctly and working correctly I should just not worry about it, but this is really bugging me. I have spent many hours searching and researching just to get to the point I am now with everything working as it should and I really can't find any kind of explanation or much info at all for this anywhere so I just thought to ask here as maybe someone can shed some light on the subject here. any input would be greatly appreciated... should I just be satisfied that I was able to make a post processor that is working fine or should I really do some more digging? I have really just about run out of places to dig at this point though