<p>I have an Anet A8, and recently updated the firmware to Marlin 1.1.8.
My only change was replacing the configuration files by the Anet A8 sample files built in with the firmware zip file.</p>

<p>Everything works fine but, sometimes, right after finishing a printing (while doing the "home all"), the LCD shows some weird data, like this:</p>

<p><a href="https://i.stack.imgur.com/8H1Vn.jpg" rel="nofollow noreferrer" title="LCD weird data"><img src="https://i.stack.imgur.com/8H1Vn.jpg" alt="LCD weird data" title="LCD weird data"></a></p>

<p>The same happens when push the "confirm", after the mesh bed leveling.<br>
I'd like to know why it happens. Is it a Marlin bug?</p>

[{'answer_id': 6283, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 4, 'selected': True, 'text': '<p>This is a known problem of the Anet A8 display, it is caused by electrical interference. Pressing the middle button will refresh the display.</p>\n\n<p>This is prone to happen when doing long prints. </p>\n\n<p>There are some reported successes of people inserting ferrite beads or toroidal rings. </p>\n\n<p>No, this is not a firmware issue, this is a hardware issue.</p>\n'}, {'answer_id': 6468, 'author': 'Gianluca', 'author_id': 12439, 'author_profile': 'https://3dprinting.stackexchange.com/users/12439', 'pm_score': 2, 'selected': False, 'text': '<p>I have solved completely, I covered the flat cable, with copper tape, this shield should be connected to the 0V of the power supply.\nAll disorders will disappear.</p>\n'}, {'answer_id': 11172, 'author': 'Jacob', 'author_id': 18827, 'author_profile': 'https://3dprinting.stackexchange.com/users/18827', 'pm_score': 2, 'selected': False, 'text': '<p>I had this issue for a long time and finally I tried a super-simple hack. Attach a testlead from bed to PSU (which is grounded). Problem solved!</p>\n\n<p>In other words: The Marlin firmware may be more "sensitive" than the original stock firmware, but it is not really a firmware issue.</p>\n\n<p><a href="https://i.stack.imgur.com/e3klX.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/e3klX.jpg" alt="enter image description here"></a></p>\n'}]
['https://3dprinting.stackexchange.com/questions/6281', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/11246/']