On Sun, 27 Jan 2013, Kip wrote: > Greetings all! My shift registers seem to be working well as a cheap > and easy port expander! Apologies for how long it took me to write it > up, but we are currently in the middle of the FIRST Robotics Challenge > build season, so I'm spending almost every evening mentoring high school > students. > > I've attached a schematic of the circuit used. Notice it creates 16 > output and 16 input lines using only 3 output and 1 input pin on the > parallel port. > > I also attached the .comp file to drive it. It count base-thread ticks > for timing. I have it configured to update every 1 ms with my system, > but this is configurable. While 1 ms is too slow for micro-stepping, it > is plenty fast enough to detect the pulses from my cooling fan > tachometers, turning pumps on and off, reading control panel buttons, > and blinking status LEDs. > > The complete write-up can be found here: > > http://www.shafferhouse.org/linuxcnc/LinuxCNCShiftRegisters.pdf > > It goes into a lot of detail that is probably too basic for most of the > readers of this list, but please let me know if there are things you > would like me to add. >
can someone suggest a source for the 74ls595 and 74ls597 ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
