Hello all, I have been working on a series of tutorial videos on YouTube on CNC for the Home Hobbyist. In the tutorial I am currently working on, I am discussing the parallel port. I want to give as accurate information as I am able. My question is about the documentation found at [ http://linuxcnc.org/docs/2.7/html/hal/parallel-port.html | http://linuxcnc.org/docs/2.7/html/hal/parallel-port.html ] This documentation primarily talks about adding additional Parallel ports to LCNC. It states that there are three modes in which LCNC can use a PP. These are in, out and x. It also provides a chart showing the pin direction based on the mode that the port is set in.
On this chart or table, it shows for the "in" column that pin 14 is an input pin. I think this is in error and should be labelled as an output. To test my theory, I installed a second PCI PP in a computer and run the stepper config wizard. I set up the first port as output and the second as input. In both output modes and input modes (for the ports) pin 14 is labelled as an output pin. This would make sense considering that pins 1, 14, 16 and 17 belong to the control group. So if this is correct, then the documentation needs to be updated to reflect that. If I am incorrect, can someone explain why this pin is input when the mode is set to input? I also understand that in mode x, that the control port (pins 1, 14, 16 and 17) are set to inputs but at risk because the physical pins on the port may not be open collector. If you are interested, the play list for the tutorials can be found here: [ https://www.youtube.com/playlist?list=PLaamliiI72ntlrHKIFjh2VjmehRGgZpjm | https://www.youtube.com/playlist?list=PLaamliiI72ntlrHKIFjh2VjmehRGgZpjm ] I have 9 tutorials there and working on number 10. The idea behind them is to give enough information over time that a new hobbyist can get into some form of CNC. Rather than giving specific case examples, I want the information to be applicable to whatever they are wanting to set up. Router, mill, plasma, lathe, 3D printer or whatever. Constructive criticism is welcome, but I do give a disclaimer. I am not a teacher, engineer or a machinist. Just a home hobbyist who wants to give back to the community. Thanks for your help and input. It is greatly appreciated. Joe Hildreth ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
