Here's some info on the DNA20 and its functions. A few people have asked me about this so I thought I would post this info in the thread.
Normal Operation
Watt setting: The power level currently set on the DNA 20D.
Battery indicator: The current state of charge of the battery.
Volts display: The current or most recent output voltage being supplied to the atomizer.
Ohms display: The resistance of the atomizer attached to the device. This is measured only when the
unit is supplying power to the atomizer. At other times, it shows the most recent measurement.
Other modes
Locked mode: Pressing the fire button five times with less than .7 seconds between presses will cause
the device to enter Locked mode. In Locked mode, the device will not fire and the output power will not
adjust accidentally. While in Locked mode, the screen will be off, except that pressing a button will show
Locked, Click 5X. To exit Locked mode, press the fire button 5 times.
Stealth mode: While locked, pressing the fire and down buttons simultaneously for five seconds will
switch to stealth mode. In this mode the display is off. It will still show error messages and the Locked,
Click 5X advisory. To switch back to normal display mode, from locked mode hold down the fire and
down buttons simultaneously for 5 seconds. This setting is stored to internal flash memory, and remains
if power is removed.
Right Mode and Left Mode: While locked, holding the fire and up buttons simultaneously for 5 seconds
flips the display. This allows for maximum flexibility in designing the mod, as well as accommodating left
handed vapers. This setting is stored to internal flash memory, and remains if power is removed. Please
note that if using a potentiometer instead of a button, this option is not available. However, it can be set
before soldering the potentiometer on during manufacture.
Error Messages
The DNA 20 will indicate a variety of error states.
Check Atomizer: The DNA does not detect an atomizer, or the atomizer has shorted out.
Shorted: The atomizer or wiring are short circuited.
Check Battery: The battery is below 3.1 volts. It probably needs to be charged.
Weak Battery: The battery sags excessively when firing. This typically means the user is not using a high
rate battery, or the battery is old and degraded. It can also mean the battery is not making good contact.
Too Hot: The DNA 20D has onboard temperature sensing. It will shut down and display this message if
the internal board temperature becomes excessive.
Too low power setting: The DNA 20D puts out a minimum of 4 volts. With low power settings (7 to 8
watts) and low resistance atomizers (below 2 ohms) the DNA will sometimes be unable to provide a low
enough power output to be power regulating. If this is the case, the Ohms display will be flashing. The
device will still operate.
Auto power down
The screen will be at full brightness while firing. After 15 seconds with no button presses, the screen will
dim. 4 minutes after the last button press, the screen will fade out and the device will go to sleep mode.
Pressing any button will turn the device and display back on.
Some of these woods definitely have some strange names. lol 
