Andy, The 7I43 can also do PWM/DIR and handle the encoder counting to run servos.
Alan On Oct 11, 2013, at 4:23 AM, [email protected] wrote: > From: andy pugh <[email protected]> > Subject: Re: [Emc-users] BBB & LinuxCNC. > Date: October 11, 2013 3:22:58 AM PDT > To: "Enhanced Machine Controller (EMC)" <[email protected]> > Reply-To: "Enhanced Machine Controller \(EMC\)" > <[email protected]> > > > On 11 October 2013 04:11, Condit Alan <[email protected]> wrote: >> I am kind of like Ralph. I also have a Mesa 7i43 that I would like to be >> able to run from a BBB. It would be great if there was a cape that could >> look like an EPP with a driver that could run hostmot2. >> >> I have one machine that I am going to try to run from the BBB + BeBoPr + >> Bridge. But eventually I would like to use my 7i43 with a BBB or, if Pete >> comes up with the equivalent of a 5i25 for the BBB, sell my 7i43 and the two >> 7i42TAs that I have. > > This is quite a complicated situation, and there seems to be some > confusion about the datatypes of the various layers. > > I don't think an EPP interface out of the BBB and into the 7i43 makes > much sense. The 7i43 takes commands from the EPP and produces step/dir > and/or PWM and/or GPIO signals from that. > This means that a BBB to EPP interface would probably be using the PRU > to prestend to be an EPP parallel port to tell a 7i43 to do exactly > what the PRU _already_does_ . > > What would be much more interesting would be a Smart-Serial module in > the BBB PRU. Then the 7i76 could connect directly to a 25-pin D-sub on > a BBB cape, with step/dir sourced from the PRU, and the GPIO handled > by Smart-Serial. > > The other alternative would be an adapter board to link PRU step/dir > or PWM to the 50-pin headers on the 7i42 cards. I am not sure if the > 7i42 can work as a level-shifter, I do know that the FPGA on the Mesa > cards is 3.3V like the BBB but I am not sure which side of the ribbon > cable the level-shifting is done. > > -- > atp > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60134071&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
