Hello Guest it is November 14, 2019, 11:08:02 AM

Author Topic: !!! glitches in step pulse train in pulse engine when charge pump enabled !!!  (Read 3111 times)

0 Members and 1 Guest are viewing this topic.


there is a issue with step pulses when charge pump is enabled in pulse engine.

tested with mach3 v3.043.066 (demo).
measured on pin 46 (step out - x) with commands "G01 X10", "G01 X0".
tested with firmware 3.0.46 and also with 3.0.48. same issue.

normaly G01 generates pulse train with period 16ms (see "pishtak_normal.jpg").
pulse width is 20us. no problems when charge pump is DISABLED.

as soon as i ENABLE charge pump on pin 53 in pulse engine,
there are glithes in pulse train. this happens randomly.

glitch looks like on "pishtak_glitch1.jpg". total width is 1ms.
"pishtak_glitch2.jpg" and "pishtak_glitch3.jpg" is zoomed to the beginning of the glitch.

as you can see, the glitch is visible on oscilloscope, you can hear it
and also feel it when touching stepper motor.

trigger of the oscilloscope is setup so it detects positive pulse with width larger than 100us.
didn't measured Y and Z pulses but these glitches also happens
on Y and Z axis (you can hear it and feel it).

can you check it ?



Offline NeoTO

  •  504 504
    • View Profile
    • PoLabs
Please check whether this glitch has been resolved with update 3.0.55.
www.poscope.com home of PoKeys USB HID, IO, USB, Ethernet controler and PoScope USB PC oscilloscope

Tested lastest version v3.0.56. It looks charge pump issue (glitches in pulse train) is fixed.
No more glitches like on oscilloscope pictures I provided previously.
Charge pump is now correctly generated only when Mach3 is connected
and is not in reset state (E-Stop).

In General Config there is option to generate charge pump even Mach3 is in reset state (E-Stop).
This is not implemented yet I think, so maybe would be good to implement it.

One cosmetic thing. When Charge pump is stopped for example with pressing
Reset button, pin53 can be either 0V or +3.3V. Everytime charge pump is stopped
it randomly stays at 0V (LO) or +3.3V (HI). No problem at all, but would be nice
to have it always at defined level (LO or HI).

Thanks for great support

Best Regards