Originally Posted by Dennis Bohlke  The problem of going from DXF or HPGL to step and direction signals at the parallel port is not a trivial task.
Took me a few months to get the HPGL conversion working, it is easier because it works with integers for amounts of movement. But that was in the DOS era.
After fifteen years I think I pretty much got it the way I originally wanted.
The timing part of creating the step signals is very difficult and with an Windows host computer it's almost always subject to being messed with by the operating system.
You should look into the EMC program. It's open source and has a motion engine you could adapt to. It works with Linux.
Dennis
www.super-tech.com |
Thanks for the reply Dennis !
You mean it took you fifteen years to achive it ? (wow man, i don't have that time)
I'm thinking about using the inpout32.dll for "talking" to the parallel port under Win Xp & i'm not planning to go over 2000Hz on a 200step motor so i think & hope it'll be ok, what do you think ?
I'm stuck with windows because a lot of people are using it including my "school" & have no linux programming skills (not yet).
My first concept was to represent the paper as an array or matrix of dots (dot/nodot)
and to get the head to print dots on each line. The cylinder feeds(changes) the lines to be printed by the pen, but no turning back, what HPGL doesn't permit(from what i understood a few minuts ago). Anyone has an idea on how to do it & about the aproriate file format to use ?
Thanks !
Superman
Sorry, from here I am not much help
The "roland" was only a suggestion as a step forward as an example
not knowing what your application is to be used for, drawing size, etc.
I have used "roland" plotters on flat beds and drum in a previous job for accurate plots for customer samples and cutting "ruby" sheets for photographic purposes
I thought it may be of use to you.
My application required the bed and drum to be bi-directional for speed and accuracy of the plot ( ie accuracy to 1/2 the line thickness to overlay onto photo negatives and die-lines to suit the customer requirements ) |
Thanks Superman, thanks to you i know that HPGL doesn't suite my needs & it takes me a step further in my searching.
My machine doesn't need much accuracy, +-1mm would be enough. the paper size is approx 600mm wide by n millimeters long that's why i need the cylinder to turn in only one direction imagine the time it would take to draw a 500mm square with a 400mm dia circle inside the square or a 1000mm*550mm rectangle instead of the square ...etc HPGL provides "high" accuracy & i need "speed".
Thanks !
cnc2.