> amplifiers. The scope should have at least 100mhz bandwidth and the probes > should be precalibrated so that the test square wave on the front of the > scope is indeed square and flat top and bottom when observed. It is & they are. Tek 475 with switchable probes.
> Also, do not use probes without the 10x attenuation enabled as the added > capacitance of a direct probe may|will also total the amplifiers. Ah, glad you reminded me of that. By the time I would have gotten the vert gain low enough for the trace to be on the screen, <poof!>. > Informational wise for this sort of troubleshooting, scoping the step and dir > signals *to* the amplifier, and comparing the rise times, steplen times and > dir setup times to what the amplifiers need will probably be far more > usefull. A parport that doesn't have adequate drive will be not only slow, > particularly the pullup times, but may not have the source and sink current > cajones to satisfy the amplifiers input voltage requirements even with > arbitrarily long steps. This is not an uncommon problem. Excellent! The PC is a mini-desktop. Most of which are a "laptop-in-a-box" and have wimpy parports. I'll put the scope on the inputs of the stepper controller. For some reason, I expect to see not-so-square pulses. It also has a PCI parport card being used for switches, LEDs, etc. It would be easy enough to switch the plugs and transpose parport.0 and parport.1 throught the hal & ini files. I'll replace the PC-controller cable too. It's just a dirty old generic printer cable. Probably not even IEEE-1284. Anyway, I've been playing with parameters in 2.2.1 that weren't available in 2.0.1 and have made some improvements. Just found the rest of the info on steplen, stepspace, dirhold & dirsetup that I didn't have. Looks interesting. But it's 1045PM, cold and raining so I'll just wait till tomorrow. Thanks again, > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users -- Emory Smith [EMAIL PROTECTED] http://defoliants.googlepages.com ------------------------------------------------------------------------- SF.Net email is sponsored by: Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
