> On Feb 1, 2019, at 10:48 PM, Chris Albertson <albertson.ch...@gmail.com> > wrote: > > One plan would be to use a purpose designed keyboard scanner chip. This > would have a serial I2C output that sends data when a button is pressed. > There are MANY such chips available. > I didn’t think of that. How would I connect an i2C device? This input panel includes the start, stop, jog, … I am still inclined to use the 7i73 keyboard scanner but I am intrigued because the 7i73 manual appears to state that it only allows one keypress at a time to avoid phantom keystrokes. I would like to have a 2-key rollover. Can anyone confirm how the 7i73 treats simultaneous keys?
> On Fri, Feb 1, 2019 at 7:05 PM Thaddeus Waldner <thadw...@gmail.com> wrote: > >> I am in the process of installing a manual control panel on my router, >> using a MESA 7i73 pendent card. The panel has a 5x6 button matrix and 16 >> LED indicators. I am driving the LED indicators with a pair of 74HC573 >> 8-bit latch. I had initially planned on wiring each buffer input to a >> corresponding output on the MESA 7i73 >> . >> However, after mapping out the keys, I discovered that this is not >> possible becuase the 23 keys on my panel are arranged in a 5x6 matrix, >> which requires that I configure the MESA 7i73 for an 8x8 keypad. This >> leaves me with 14 outputs total; 2 short. >> >> One option that I think I have is to connect the inputs of both latch >> chips to the same 8 outputs and use the latch enable on each chip. >> >> I have no idea how I would implement a latching buffer scheme in the >> LinuxCNC HAL. Can anyone help me with that? >> >> I am using the 74HC573 devices because I have them on hand. Would it be >> simpler to use a 74HC154 demultiplexer instead? >> >> Thaddeus Waldner >> >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > > -- > > Chris Albertson > Redondo Beach, California > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
