Testing my Accelerometer Sensor
I followed the directions to quickly test the sensor:
"Plug into port 1 of your NXT brick and slect VIEW - Ultrasonic cm - PORT 1. As you tilt the sensor up and down, you'll notice that the readings will change..."
But this was not the case on my NXT. Thinking it could be the port, I tried all the standard sensors and they all checked out OK. Went to the Lego Site and no help there, so I went to the manufacturer website (www.hitechnic.com) and found a comment that said:
"NXT Firmware version 1.03 must be loaded in the NXT for the compass to operate correctly. You can check the firmware version by displaying the NXT Window in the Mindstorms software."
This statement was on the bottom of the "more information" page of the ACCELEROMETER SENSOR page, not the compass (so I assume that it was a typo).
I found that I was on ver 1.01 so I upgraded to 1.05.
The sensor started reading correctly.
Then I downloaded the Acceleration Sensor Block from the www.hitechnic.com website and followed the readme to install the control blocks into the Lego Mindstorm NXT Software.