turning on (even disconnected) hotend heater changes behavior of proximity sensor (1.0.0dev)

Liebe Kollegen, 
I have used version 1.0.0 dev but several days ago after reloading it the suspected bug appeared.
Hardware: motherboard MKS Gen-2Z v1.1. Capacitive proximity sensor, LJC12A3-5-B/ZX, connected to Ymax endstop with voltage divider 6.3 kOhm, has 12.03V on it. It is in High state (5 V) when untriggered, when triggered goes to Low. Ymax endstop is disabled. ENDSTOP_PULLUP_Y_MAX is "not installed". 
Sensor works fine in any conditions except when the hotend heater is turned on. When it is on the sensor detection range increases by 2-5 mm. And detection border is not a border anymore but a range: sensor turns on at 2 mm distance and goes off at 5 mm distance. To be turned on again it needs to go to 2 mm distance to the bed. 
It is not a hardware problem. The sensor was changed to brand new one, all power consumers were disconnected and hotend heater also. I made sure the voltage on the sensor was 12.03V at the heater on and off also. I have changed the sensor signal pin
from Ymax to D2. But whenever you turn on disconnected hotend heater the sensor increases its range and the triggering border becomes a range, despite voltage on sensor is exactly the same. 

== If the firmware is changed to v0.92 (with same configuration.h file)the problem disappears. ==

I tried to get back to v 1.0.0 but can't do it because the sketch compiles with error: 

In file included from sketch/ui.cpp:34:0:
sketch/uimenu.h:1379:0: warning: "UI_MENU_PREHEAT_CNT" redefined
sketch/uimenu.h:976:0: note: this is the location of the previous definition

So, please pay attention on this possible bug in 1.0.0dev and secondly, 
what could be changed in configuration to get rid of this compilation error. Then I would be able to test if the bug is reproducible in  v1.0.0

Thank you for your support!  


  • Guys, sorry, I've found the bug and it isn't yours. My PSU and aluminium table are connected to the same ground. The PSU sent there some "noise" which triggered sensor on a longer distance from table. So, problem is solved. 

    But I would anyway kindly ask you to let me know what could be done with the above-mentioned compilation error so that I could use stable v1.0.0. 

    Thank you for being there and supporting.
  • That is no compilation error, it is a warning. I think I have already fixed in on github and at weekend I will update config tool, but you can safely ignore it.
  • Thank you!
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