On Sat, 10 Mar 2018 13:53:29 -0500 Gene Heskett <ghesk...@shentel.net> wrote:
> On Saturday 10 March 2018 12:42:56 Nicklas Karlsson wrote: > > > I just discovered it take about 200µs to write six bytes of process > > data in process RAM via SPI into the LAN9252 chip! It's horrible slow. > > I can't figure out they think about then they make SPI protocol like > > this. > > > > Write adresse(s) and read/write as many bytes as needed had been the > > most obvious, now there are several commands and wait in between. > > > Wow! Thats time to call a surveyor and have him set stakes! > > But from what little I've fooled with spi, on a pi 3b no less, its many*2 > faster than that. I have it writing to a Mesa 7i90HD at 41 megabaud, and > reading the responses back from the 7i90HD at 25 megabaud. Sending and > receiving in 32 bit packets. SPI is 5 or 10Mbit/s I think and faster is possible, problem is procedure needed to read and write data to process ram. Distributed clock and real time data work perfect. ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
