<p>I have a Tronxy P802M (very similar to the Anet A8, but using a Melzi2.0V5 board) that seems to work fine (I just finished building, and axes movement and the integrated display work) but when I try to connect to the printer from my Simplify3D on Windows 10, I get the following:</p>

<pre><code>[...]
  Connected to machine!
SENT: T0
READ: ok 0
READ: wait
SENT: M105
READ: ok 0
READ: T:24.44 /0 B:23.33 /0 B@:0 @:0
  Connection failed.
</code></pre>

<p>My other printers all connect fine.</p>

[{'answer_id': 3504, 'author': 'brandstaetter', 'author_id': 5758, 'author_profile': 'https://3dprinting.stackexchange.com/users/5758', 'pm_score': 2, 'selected': True, 'text': '<p>The <a href="https://www.simplify3d.com/support/faq/#faq-4630" rel="nofollow noreferrer">Simplify3D support site</a> mentions to disable the "wait for startup command" option in the firmware configuration for S3D.</p>\n\n<p>This allows me to make a rudimentary connection to control the printer, however e.g. during the bed levelling wizard of S3D, the connection still breaks off.</p>\n\n<p>It works reliably with Octoprint. I\'ll consider that good enough.</p>\n'}, {'answer_id': 3505, 'author': 'TafT', 'author_id': 4437, 'author_profile': 'https://3dprinting.stackexchange.com/users/4437', 'pm_score': 1, 'selected': False, 'text': '<p>If you are using a USB 3 port to connect the printer to your PC, try connecting via a USB 2 hub.  </p>\n\n<p>My Vector 3 will not work on a USB 3 port, only on a USB 2 or lower.  The device correctly mounts and presents but serial communication fails.  One of my laptops only has USB 3 ports on it, so to work around the limitation I connect via a cheap USB 2 hub. </p>\n\n<p>I have heard that many 3D printers use a similar USB to UART / serial connector chip and that they suffer from similar limitations as a result.  </p>\n'}, {'answer_id': 3998, 'author': '3d noob', 'author_id': 6999, 'author_profile': 'https://3dprinting.stackexchange.com/users/6999', 'pm_score': -1, 'selected': False, 'text': '<p>Try changing your port in the control menu. By default, mine is set to <code>COM 1</code> and I have to change it to <code>COM 3</code>.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/3470', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/5758/']