Since then, several programs use that value directly to test whether the mouse has been scrolled down or up (delta / 120 = 1 -> down, delta / 120 = -1 -> up, or something like that). This is an arbitrary value that has been chosen by Microsoft in the past to allow finer control. Most (almost all) mouse drivers cause mouse wheel events with a 'delta' of ☑20.
it doesn't work as expected if I use the wireless mouse of the Microsoft Wireless Desktop 800 kit ( ).mouse wheel works if I use a standard USB mouse.In the past I found the same problem in other softwares, and I've already discovered the reason: I've just updated LabVIEW to version 2011 on my Windows 7 64-bit machine and I discovered a severe bug: the mouse scroll wheel doesn't work as expected (i.e.
