Software, the OS and interrupts
| English | Chinese | Pinyin |
|---|---|---|
| software | 软件 | ruǎn jiàn |
| operating system | 操作系统 | cāo zuò xì tǒng |
| hardware | 硬件 | yìng jiàn |
| system software | 系统软件 | xì tǒng ruǎn jiàn |
| application software | 应用软件 | yìng yòng ruǎn jiàn |
| device drivers | 设备驱动程序 | shè bèi qū dòng chéng xù |
| utility software | 实用程序 | shí yòng chéng xù |
| interrupt | 中断 | zhōng duàn |
| multitasking | 多任务处理 | duō rèn wù chǔ lǐ |
Software 软件 and the operating system 操作系统
- Hardware 硬件 is the physical parts; software is the programs that control them.
- Software splits into system software 系统软件 and application software 应用软件.
- The most important system software is the operating system.
System vs application software
- System software controls the computer and gives a base for other programs: the operating system, compilers, device drivers 设备驱动程序, and utility software 实用程序 (anti-virus, backup).
- Application software lets the user do a task: word processor, spreadsheet, database, web browser.
- System software runs in the background; application software is used directly by the user.
Software divides into system software (runs the computer) and application software (lets the user do a task).
On an interrupt 中断 the CPU saves its place, runs the interrupt service routine, then restores its place and carries on.
Which is system software?
The OS (and drivers, utilities) is system software; the others are application software.
Sort these into system or application software.
Drivers and utilities run the computer (system); a browser is a user application.
The operating system
- The OS controls the whole computer so the hardware, applications and user work together. Its roles include:
- managing files, managing memory, managing peripherals (and drivers), multitasking 多任务处理, handling interrupts, providing a user interface, a platform for applications, and security.
The motherboard and the parts attached to it are hardware — the physical parts of a computer.
Which is a role of the operating system?
The OS manages files, memory, peripherals, multitasking, interrupts, the UI and security.
Interrupts
- An interrupt is a signal to the processor that something needs attention now.
- It can come from hardware (a key pressed, printer out of paper), software (divide by zero), or the user (pressing cancel).
- The processor stops, saves its place, services the interrupt, then resumes — so the computer reacts quickly to important events.
The operating system sits between the hardware and the application software and user, letting them work together.
How the CPU handles an interrupt
Step through an interrupt. The CPU pauses what it's doing, deals with the urgent event, then carries on exactly where it left off — which is how one processor juggles the keyboard, printer and timer at once.
An interrupt is:
An interrupt makes the CPU pause, service the event, then resume — for quick reactions.
A hardware interrupt comes from a device (e.g. a printer out of paper), while a software interrupt comes from a program (e.g. dividing by zero) — both make the CPU pause and service the event.
Interrupts can be hardware, software or user-triggered; in every case the CPU saves state, handles it, then resumes.
You've got it
- system software runs the computer (OS, drivers, utilities); application software does a user task
- the OS manages files, memory, peripherals, multitasking, interrupts, the UI and security
- an interrupt = a signal needing immediate attention (hardware / software / user)
- on an interrupt the CPU saves its place, services it, then carries on