>> >> AFAIK there are no significant issues with HM2 encoder velocity >> estimation >> >> Heres a 100 Hz quadrature velocity trace: >> >> http://freeby.mesanet.com/100_Hz_quadrature_velocity.png >> >> Notice theres no discernible ripple in the velocity even though theres >> considerable sample jitter (green trace) >> > Show me that same trace out of a 7i90 running on the spi bus driven by > the rpi 3b.
I expect it would be the same since all hm2 encoder counters are the same regardless of interface, and AFAIK the encoder driver code above the data transfer level is the same for all interface methods. If you wish to determine if your error is driver/SPI hardware _or_ simply bad quadrature you can use a hardware stepgen in velocity mode looped back to the encoder counter since it generates basically perfect quadrature. If this generates noisy velocity signals then the driver/SPI interface needs to be looked into. Peter Wallace Mesa Electronics ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
