T-Kernel Specification (1.B0.02)

2 CHAPTER 1. T-KERNEL OVERVIEW
• Time management functions
• Subsystem management functions
T-Kernel System Manager (T-Kernel/SM) provides the following kinds of functions.
• System memory management functions
• Address space management functions
• Device management functions
• Interrupt management functions
• I/O port access support functions
• Power management functions
• System configuration information management functions
T-Kernel Debugger Support (T-Kernel/DS) provides the following kinds of functions exclusively for
debugging use.
• Kernel internal state reference
• Trace
1.2 Scalability
T-Kernel is a real-time kernel for embedded system use, applicable to a wide range of systems large and
small. It is aimed at enhancing portability of software such as device drivers and middleware.
The T-Kernel specification is designed to be applicable even to large-scale systems. The approach of
defining subsets to this end, with functions specified in some subsets but not mandatory in others for
small-scale systems, has the disadvantage of hampering portability of device drivers, middleware and
other software. Functional requirements also vary widely from one target system to another, making it
difficult to settle on workable subset specifications.
The T-Kernel specification does not adopt a level division or other subsetting approach. In principle,
all operating systems compliant with the T-Kernel specification must implement the specification in
it entirety. A target system, however, that does not need all the OS functions is free to implement a
scaled-down version of the OS. It is also acceptable to offer T-Kernel users the option of leaving out
functions not used in a target system. The important point here is that it is the user, not the OS
provider, who decides which functions to omit.
T-Kernel providers
• The entire specification must be implemented.
target systems are allowed.
Scaled-down implementations for specific
• Providing users with the means for removing or skipping unnecessary functions is also allowed.
Middleware providers
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T-Kernel 1.B0.02