RTS WM300 Especificaciones descargar pdf (Pagina 39)

Chapter 2 Specification of Communication port for CPU module

2 – 25

Cautionary note

In communication (Task code processing and ASR communication) of EHV-CPU series, the response may delay if

CPU is loaded. We would explain a load of CPU below. Please utilize this as a standard in considering the

responsibility of communications.

[About Communication processing time in CPU module]

CPU module executes processing by two processors, one is an operation processor to execute user programs and the

other is a main processor to execute a system program processing, and END processing and a communication

processing. While the operation processor executes the user program, the main processor executes the communication

processing. Therefore, a total of scan time and system processing time is communication processing time.

Taking 40ms which is a minimum transmission interval of ASR communication for instance, a rate of time for each

processing executed by the main processor is shown below. In this case, response delay and transmission delay occur

at least unless task code communication and ASR communication are completed within approx. 28ms for

communication processing.

*1. 1ms cyclic processing. In this case, it is executed 40 times.

*2. Processing time when the number of program steps is 0

*3. Processing time when the number of I/O mounted is 66 words (1056 points, that is 66 modules equipped 16-

oint I/O

each are mounted.)

System

program

processing

6.4 [ms]

(Fixed) *1

Communication processing (Task code communication, ASR

communication)

Scan time + System processing time

28.7 [ms]

(Fluctuation)

END processing 2.7ms (Fluctuation) *2

I/O refresh processing 2.2ms (Fluctuation) *3

Processing time 40ms

Figure 2.24 An example of ratio of each processing by main processor within 40ms

Communication processing time is not fixed but fluctuates under the influence of the following factors.

(a) Scan time of user program

While the operation processor executes the user program, the main processor can execute the system processing

and the communication processing. The longer scan time becomes, the more communication processing time

increases. And since the number of times that END processing occurs within a same time also decreases if scan

time get longer, END processing decreases and communication processing time increases in above figure.

(b) I/O configuration

I/O refresh processing time increases and communication processing time increases in proportion to the number of

modules mounted. It takes 1µs per word as processing time depending on the external I/O points and the number of

link data.

This is a setable time, using operation parameter of Control Editor. This “System processing” means the

communication time.

1 2 ... 34 35 36 37 38 39 40 41 42 43 44 ... 66 67

Comentarios a estos manuales

Sin comentarios

RTS WM300 Especificaciones Pagina 39

Comentarios a estos manuales

Relacionado con productos y manuales para Sistemas de intercomunicación de la puerta RTS WM300