 PALcode

In computing, in the Alpha instruction set architecture, PALcode (Privileged Architecture Library code) is the name used by DEC for a set of functions in the SRM or AlphaBIOS firmware, providing a hardware abstraction layer for system software, covering features such as cache management, translation lookaside buffer (TLB) miss handling, interrupt handling and exception handling.PALcode is Alpha machine code, running in a special mode that also allows access to internal registers specific to the particular Alpha processor implementation.