Greetings
-----Original Message----- From: Charles Steinkuehler [mailto:char...@steinkuehler.net] There are far too many pin naming schemes for the BeagleBone, including two new ones used by the LinuxCNC Beaglebone code. Short answer: ============ Read the code (sorry!) Medium answer: ============ The PRU code uses an integer value that equals the kernel GPIO number plus 32 (so that zero means "don't twiddle *ANY* pins!"). The values are also extended, and what would be the non-existing GPIO bank 4 means "Use the PRU direct I/O pins". The hal_bb_gpio pin numbers is: 1xx = P8 2xx = P9 xx = connector pin number Long Answer: ============ I really need to make a blog page about pin numbering. There's some data in Brandon Heller's post about home/limit switches: <http://bb-lcnc.blogspot.com/2013/07/adding-homelimit-switches.html> http://bb-lcnc.blogspot.com/2013/07/adding-homelimit-switches.html I'll try to get something posted tonight... -- Charles Steinkuehler Thank you for this information. After some "code reading" the .dts file for the BeBoPr-bridge got me to the existing pinouts for stepping. For new inputs, I need to work through Brandon's stuff on my system. The para: We'll use X-Max, the limit switch closest to the PWM outputs at the edge of the BeBoPr. According to the BeBoPr manual, the BeagleBone black manual (BBB_SRM.pdf pg 80), and tracing the board traces, the X-max input switch is pin 32 on connector 8 and gpio0.11. has me puzzled. I cannot find the BeBoPr manual anywhere on CircuitCo and have not got one (or a Bridge) to trace tracks :-( The .dts file suggests Brandon's numbers are non-Bridge and X-max will be P8-9 (gpio2.5) Finally a detailed question: I notice on the 'scope that the DIR lines have random looking waveforms (around 500 Hz - but different patterns on each axis) after a keyboard jog has stopped. An axis DIR goes quiet (at LO) after a G-code move of the axis. Is this behaviour intentional? If not might it hide a bug on Setup/Hold times of the DIR line - I ask as in another life I have been bitten by the small, but very nasty to find, loss of position errors that invalid timing can produce on some stepper drivers? Best wishes John Prentice ------------------------------------------------------------------------------ Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! Discover the easy way to master current and previous Microsoft technologies and advance your career. Get an incredible 1,500+ hours of step-by-step tutorial videos with LearnDevNow. Subscribe today and save! http://pubads.g.doubleclick.net/gampad/clk?id=58041391&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
