Select the way device buttons are mapped into pointer button events.
When a device is acting as the pointer, Accelerated-X uses the button map to translate the button event into a pointer event that the application receives. You can map a device button to one of the 5 pointer buttons, or disable it. Select the device button in the list, then use the menu to select the pointer button, or Disabled.
Use the Grab... button to determine which device button corresponds to a button number in the list. Press the grab button, then press a device button. Xsetup will highlight the device button that was pressed in the list.
For mice that have scroll wheels, you can select the pointer event an application receives when the wheel is rotated. The Scroll wheel mode must be set to Button, and the device must be acting as the pointer.
Select the wheel number in the list and then use the Increase and Decrease menus to select the pointer buttons.