Why Won’t the Data Logger Respond to Any Button Presses?

Causes and Troubleshooting:

1. Unit may be ""locked up.” Try removing the battery and unplugging the adapter (if applicable). Replace the battery and plug in the adapter after a few moments. If the battery is dead, replace it with a new battery.
2. Is the unit displaying the large characters instead of the graph view? All keys are disabled when displaying the large real time characters. If the graph has reached the end of the screen, when a new pixel is drawn, the unit will blank the screen and redraw the graph shifted to to the left by one pixel. This takes a few seconds to complete and the keys are disabled momentarily. 
3. If you are downloading the data, the keys disabled during download and will not function until the download is complete.
4. Does the unit come on when attempting to communicate with DicksonWare software? If so, the keypad could be unplugged or defective.