Thanks for the input Plexer.Originally Posted by plexer
This is exactly my point!
Either the GCode to Step calculations are done on the PC or they are done on the breakout board.
If they are done on the breakout board, that board will need to have a fair amount of muscle ( = expense)
If they are done on the (M$) PC and sent to the breakout board which then simply takes them (the individual step instructions) and steps the motors (in real time as seen from the perspective of the breakout board based on the receipt of instructions from the PC), then we are at the mercy of the Mr Gates and real "real time" can only be dreamed of because if the M$ OS decides to do something else, the output to the Port is delayed and que'd and when the OS is finished, the complete data que is dumpred to the port as quickly as the port can handle it. Result = step timing screwed!
On the other hand, if the (M$) PC creates the individual step instructions and sends them to the breakout board (as fast as the PC, Port Baud rate etc will allow) and they are que'd/cached on the breakout board, and the breakout board releases the instructions to the motors at the correct intervals, then the timing problem is solved.
QED