On Mon, 11 Nov 2013, Hugh Wylie wrote: > Date: Mon, 11 Nov 2013 08:19:36 +0200 > From: Hugh Wylie <[email protected]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: [email protected] > Subject: [Emc-users] Mesa 5i23 step rate limitation with concurrent pwmgen > > Four stepgens and one pwmgen are invoked in a LinuxCNC 2.5.2 environment as > follows, resulting in step rate limitation on all four joints: > > > > loadrt hm2_pci config="firmware=hm2/5i23/SVST4_8.BIT num_encoders=0 > num_pwmgens=1 num_3pwmgens=0 num_stepgens=4" > > > > Under this configuration, maximum step rate is limited to approximately > 250Hz, while without 5i23 pwmgen invocation the 4 stepgens perform as > expected (with good step rate headroom). >
What symptom do you have? Do you have the per axis Stepgen maxaccel set to 1.25 times the the per axis machine acceleration limits? If this is not done you may get following errors > Having confirmed that this limitation is independent of host motherboard but > identical on two Mesa 5i23 adapters tested, and independent of pwmgen > frequency between 400Hz and 20kHz, it is expected that this is a firmware > rather than performance constraint of the FPGA on the 5i23 adapter. The ini > file is unchanged between configs with or without 5i23 pwmgen. > I doubt that this is any kind of FPGA performance constraint (the 5I23 stepgens are capable of 12 MHZ step rates) And while stepgens mixed with PWMgens is not terribly common, its used in a lot of step/dir systems with analog controlled spindles. > > > What steps are needed to overcome this constraint? > > > > > > > > ------------------------------------------------------------------------------ > November Webinars for C, C++, Fortran Developers > Accelerate application performance with scalable programming models. Explore > techniques for threading, error checking, porting, and tuning. Get the most > from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ November Webinars for C, C++, Fortran Developers Accelerate application performance with scalable programming models. Explore techniques for threading, error checking, porting, and tuning. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
