phones, but generally the null thread puts the CPU and peripherals to sleep, after having requested a wake-up whenever the next timer is due to expire. EKA2 runs on ARM architecture CPUs and the WINS emulator. Unofficial ports exist for other CPUs. On the emulator, EKA2 provides somewhat better emulation than EKA1, more so for the APIs which Symbian OS uses to represent processes. In EKA1 they didn't work at all on the emulator, which runs as a single Windows process. Much of the credit for EKA2 goes to a single Symbian kernel engineer, who began the project as an experiment many years before it became an official part of Symbian OS. See also Nanokernel References External links https://web.archive.org/web/20091025051019/http://developer.symbian.org/wiki/index.php/Category%3AKernel_%26_Hardware_Services https://web.archive.org/web/20090717151501/http://wiki.forum.nokia.com/index.php/EPOC_Kernel_Architecture_2 http://media.wiley.com/product_data/excerpt/47/04700252/0470025247.pdf Symbian OS Operating system kernels Nanokernels Computer-related introductions in 2005