USBB17RX78K4-XXX NEC Electronics, USBB17RX78K4-XXX Datasheet - Page 12

• Manufacturer Part Number: USBB17RX78K4-XXX
• Description: 78K/4 series realtime OS
• Manufacturer: NEC Electronics

1.4 Configuration and Size of RX78K/IV
(1) Nucleus
(2) C language interface library
(3) Configurator
The RX78K/IV consists of the following three subsystems.
This is the central part of the RX78K/IV. It is embedded in the target system along with the application program
and actually carries out real-time/multi-task control. It also performs processing in response to system calls
issued from processing tasks.
The size of the nucleus differs depending on the system calls to be linked. In the case of the large model, it is
about 7K bytes MAX.; in the case of the small model, it is about 5K bytes MAX.
When the user program is described in C language, system calls are called in the format of C language calling
functions. This format, however, differs from the input format the nucleus can understand.
The C language interface library is a program that converts system calls written in C into an input format the
nucleus can understand and links the processing tasks described in C with the nucleus.
The C language interface library is described so that it can be used with the NEC’s 78K/IV series C compiler
CC78K4.
This is a tool for creating tables with information on the user system necessary for the nucleus.
The configurator runs on the development machine and can be used to input and correct the information on the
user system necessary for the OS in interactive mode.
CHAPTER 1
GENERAL
3