Cyclic Transmission Delay Time - Mitsubishi Electric MELSEC iQ-R Series User Manual

Cyclic transmission delay time

This section describes how to calculate the following cyclic transmission delay times.
• The time between the transmission source CPU module device turning on or off and the transmission destination CPU
module device turning on or off
• The time between data setting in the transmission source CPU module device and the data being stored in the transmission
destination CPU module device
In "Basic Settings" of the master station, when "Communication Period Setting" of the communication destination in "Network
Configuration Settings" is set to an option other than "Basic Period", multiply the LS (communication cycle intervals) by the
multiplier corresponding to the set option, which is specified in "Multiple Period Setting" under "Communication Period
Setting".
In this case, the multiplier is determined according to "CC-Link IE TSN Class" in "Network Configuration Settings" and
"Communication Period Setting" under "Basic Settings".
• For "CC-Link IE TSN Class B": The multiplier specified for "Multiple Period Setting" in "Basic Settings"
• For "CC-Link IE TSN Class A" when "Communication Period Setting" is "Normal-Speed": The multiplier specified for
"Multiple Period Setting" in "Basic Settings"
• For "CC-Link IE TSN Class A" when "Communication Period Setting" is "Low-Speed": The multiplier specified for "Multiple
Period Setting" in "Basic Settings"  n
The number n can be found in 'Information for slave station cyclic transmission' (Un\G1294304).
Stations with "CC-Link IE TSN Class A" where "Communication Period Setting" is set to "Low-Speed" are grouped by the
sizes of cyclic data sent from the master station to a slave station or cyclic data which the master station receives from a slave
station. The number n is determined by the number of the groups.
The procedure for calculating n is shown below.
No. Process
1 Start
2 Loop as many times as the number of
stations.
(i = 1; i  the number of stations to set;
i++)
3 Is "CC-Link IE TSN Class A" set, and is
"Communication Period Setting" set to
"Low-Speed"?
4 Calculate the values for cyclic data
(DMsi) sent from the master station to a
slave station and cyclic data (DSsi)
which the master station receives from
a slave station.
5 Loop for the maximum number of
groups.
(j = 1; j  120; j++)
Is GMsj + Dmsi  2048 true?
6
Is GSsj + DSsi  2048 true?
7
8 Update the data sizes (GMsj and GSsj)
of the assigned groups.
Branch Loop 1 Loop 2
Yes No
   
  
No.2 to
No.11
No.4 No.11

  
 
No.5 to
No.10
No.7 No.10
No.8 No.10
 
Detailed explanation
Check the stations in "Network Configuration Settings" for the
master station in the order of the No. column to assign stations
with "CC-Link IE TSN Class A" whose "Communication Period
Setting" is "Low-Speed" to groups.
Check slave stations with the No. of 1 to 120 in "Network
Configuration Settings" for the master station one by one.
(The processing of No.2 to No.11 is looped for the number of
stations.)
Check "CC-Link IE TSN Class" and "Communication Period
Setting" for the ith station in "Network Configuration Settings" for
the master station. If "CC-Link IE TSN Class A" is set and
"Communication Period Setting" is "Low-Speed", perform
processing from No.4.
If DMsi and DSsi are defined as the sizes of cyclic data sent
from the master station to a slave station and cyclic data which
the master station receives from a slave station, they are
calculated by the following formulas:
DMsi = (HBL  n1i) + (16  n2i) + ndmi
DSsi = (HBL  n3i) + (20  n4i) + ndsi
Up to 2K bytes can be allocated to a group. Determine which
group number (1 to 120) the ith station can be allocated to by
checking from the group number 1.
(The processing of No.5 to No.10 is looped for the number of
stations.)
If GMsj is defined as the total value of the data sizes of the cyclic
data sent from the master station to slave stations assigned to
the jth group, determine whether the following condition is met.
GMsj+DMsi2048
If GSsj is defined as the total value of the data sizes of the cyclic
data which the master station receives from slave stations
assigned to the jth group, determine whether the following
condition is met.
GSsj+DSsi2048
If the conditions of No.6 and No.7 are both met, update the
values of GMsj and GSsj.
Appendix 6 CC-Link IE TSN Processing Time
A
APPX
523