8-2 Data transfer required time and communication timing

(1)Required time for data transfer

Time required for a master station to communicate with all the slave stations is determined by number of connected stations and number of points of all slave stations, as well as number of data bytes of JW model special I/O modules.

T = (N + 136 x P) x 2 + 1.4P + 5.3 + 2.5 (P + 1) + α [ms] 1250

N : Total number of data bytes of all the slave station’s I/O model and JW model special I/O modules (value to be calculated by number of bytes × 8 points)

P : Number of slave stations

136 : Use 136 bits for station address on the communication format and error check function.

1250 : Baud rate; 1.25 M bit/sec.

1.4P + 5.3 : Data processing time of the master station

2.5: Total sequential send processing of the communication stations.

α: Communication time at executing remote program/remote monitor.



·If "synchronous" is selected, one scan cycle time of a PC will vary with change of transfer required time.

·Number of data bytes on the JW model special I/O module is a value set in parameter address 000600 to 000777(8) on the master station.