user48274: I have early midnight accident of my Lolin/Wemos boards. I tried uploads my sketch with a assembly VIN to GND as my reset button, when i uploads my sketch at more one hundred times, i get my boards cannot be online again or my port cannot readable to my Ubuntu as /dev/ttyXXX. usually when i plugged the Usb3.0 cable, the blink led should be turn on at my boards but i didn't get it. How  i can re-flash my boards to be online again?
Thanks in advance.

user4143: Shorting VIN to GND will over-stress the diode that is in-line with the power coming in from the USB.
The result

The diode will blow and you will not get power from the USB to power the board.
The PC may detect "over-current" and shut down the USB port
The USB port on the computer may be damaged

How do you fix it?

Replace the diode if blown.
Use a different USB port.

How do you work around it?

Provide an external 5V power source to VIN & GND if the diode is blown

How do you avoid it happening in future?

NEVER short VIN to GND, even for a short time.  There is a reset pin RST provided for the purpose of resetting the board.


48274: <p>I have early midnight accident of my Lolin/Wemos boards. I tried uploads my sketch with a assembly <code>VIN</code> to <code>GND</code> as my reset button, when i uploads my sketch at more one hundred times, i get my boards cannot be online again or my port cannot readable to my Ubuntu as <code>/dev/ttyXXX</code>. usually when i plugged the Usb3.0 cable, the blink led should be turn on at my boards but i didn't get it. How  i can re-flash my boards to be online again?</p>

<p>Thanks in advance.</p>
 4143: <p>Shorting VIN to GND will over-stress the diode that is in-line with the power coming in from the USB.</p>

<h2>The result</h2>

<ul>
<li>The diode will blow and you will not get power from the USB to power the board.</li>
<li>The PC may detect "over-current" and shut down the USB port</li>
<li>The USB port on the computer may be damaged</li>
</ul>

<h2>How do you fix it?</h2>

<ul>
<li>Replace the diode if blown.</li>
<li>Use a different USB port.</li>
</ul>

<h2>How do you work around it?</h2>

<ul>
<li>Provide an external 5V power source to VIN &amp; GND if the diode is blown</li>
</ul>

<h2>How do you avoid it happening in future?</h2>

<ul>
<li><strong>NEVER short VIN to GND, even for a short time.</strong>  There is a reset pin <strong>RST</strong> provided for the purpose of resetting the board.</li>
</ul>
