> I think SPI runs at 500 KHz. That is 50 times slower then Ethernet if you > look at only the bit rate. But what matters, I think more is the time it > takes to send one message. It might (maybe?) be faster on SPI because you > avoid the TCP/IP stack. With SPI your software is driving the bare > hardware.
SPI on cheap micro controller run in several Mbit/second, maybe 10-20Mbit is common. It is slower than Ethernet but there is nothing else where. > Sometimes a car at 55 MPH can beat a 550 MPH airplane if the trip is short > enough. I don't know about this case but it's kind of moot as 500KHz is > well more than fast enough. I think SPI on simple device may beat Ethernet on ordinary computer then it come to real time tasks. Capacity is a lot lower but it is available then needed. > > Not sure how well SPI works on the Orange Pi. Since you've decided on > > the 7i90HD with SPI why don't use use the Rpiwith it? SPI is simple stuff. It work similar to a shift register, data is clocked in and out simultaneously. It may be possible to connect several in series and then I think principle is similar to Ethercat although without possibility to insert data and checksum while shifted through. Nicklas Karlsson ------------------------------------------------------------------------------ The Command Line: Reinvented for Modern Developers Did the resurgence of CLI tooling catch you by surprise? Reconnect with the command line and become more productive. Learn the new .NET and ASP.NET CLI. Get your free copy! http://sdm.link/telerik _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
