Real-time control software first job--CNC software system case analysis

1. What are the strong real-time functional requirements of this system? Which real-time events need to be responded to in real time, and the magnitude of the allowed real-time delay is estimated.

A: After reading the file, trajectory interpolation calculation, servo control tool control, workpiece position control, decoding transmission, emergency processing, data acquisition and display, such as strong real-time functional requirements. The foreground program allows for a delay of up to a microsecond level, usually in milliseconds, when the daemon is allowed to grow.

2. If you are a software designer, to implement these real-time functions, design several real-time tasks?

A: ①NC program compilation and preprocessing ② explanation code motion trajectory interpolation operation ③ axis position loop control and software Plc④ external device communication, etc.

3. Are the time-triggered or event-triggered tasks, and if it is time-triggered, what is the period?

A: ① Event Trigger: Sudden events such as failure or emergency stop and so on. ② time Trigger: Interpolation operations, position control, fault diagnosis and other strong real-time task cycle generally in milliseconds, part processing editing processing, tool processing, speed processing, display and signal input and output of weak real-time task cycle generally in the microsecond level.

4. Are these real-time tasks independent of each other or are there certain dependencies? Analyze this dependency.

A: There is a dependency relationship, decoding-knife complement-position preprocessing-speed preprocessing-signal input and output-data display, this series of actions are in accordance with sequential cycle, fault handling, position control, interpolation operations and so on do not follow this rule, these strong real-time task priority is higher, in a broken way to insert execution.

5. Are there any shared hardware resources that need to be used between these real-time tasks? Lists this dependency.

A: Yes, these real-time tasks depend on each other, all need to share the system memory, hard disk, CPU and other devices, periodic tasks in accordance with the time-slice rotation method, the priority of the task in a broken way to execute.

Real-time control software first job--CNC software system case analysis