![background image](http://html1.mh-extra.com/html/omron/grt1-crt-05-2008/grt1-crt-05-2008_operation-manual_742290112.webp)
93
Performance of Message Communications
Section 8-2
8-2
Performance of Message Communications
This section tells you about the performance of message communications
between the CompoNet network and a SmartSlice I/O Terminal.
8-2-1
Message Communications Time
The message communications time is the time from starting to send a mes-
sage on the CompoNet network until the SmartSlice I/O Terminal receives the
message. You send data messages with the SEND instruction and receive
data messages with the RECV instruction. You send FINS command mes-
sages with the CMND instruction.
Message Communications Time to the CompoNet Communications Unit
Use the following equation to get an estimate of the message communications
time to the CompoNet Communications Unit.
Message communications time = Communications cycle time of CompoNet
network (T
NetCyc
)
×
{(Number of message bytes + 15)
÷
6 + 1}
The number of message bytes includes all bytes for the destination node
address, service code, class ID, instance ID, attribute ID, and service data.
Refer to the
CS/CJ-series CompoNet Master Unit Operation Manual
(Cat. No.
W456) for information on this variable: Communications cycle time of Compo-
Net network (T
NetCyc
).
Message Communications Time to the SmartSlice I/O Unit
When you send a message to a SmartSlice I/O Unit, you must add the mes-
sage communications time on the SmartSlice bus to the message communi-
cations time to the CompoNet Communications Unit.
Use the following equation to get an estimate of the message communications
time on the SmartSlice bus.
Message communications time = T
SL
×
Number of frames
Number of frames = Number of message bytes
÷
30 (Round up decimal dig-
its.)
Note
(1) When using message communications, execute the communications in-
structions (SEND, RECV, and CMND) at intervals longer than the mes-
sage communications time. If a message that was sent or received is lost,
the CompoNet Master Unit will record an error in the error history. You can
read the error history with the CX-Integrator or FINS commands.
(2) This message communications time is an estimate. It is not the maximum
value. The frequency of messages, the load on the remote node, the
communications cycle time, and other factors have an effect on the mes-
sage communications time. The message communications time can be
longer than the value you calculate here if there is a high load on the
CompoNet Master Unit.
Содержание GRT1-CRT - 05-2008
Страница 1: ...CompoNet Communications Unit Cat No W476 E1 01 SmartSlice GRT1 CRT OPERATION MANUAL ...
Страница 2: ...SmartSlice GRT1 CRT CompoNet Communications Unit Operation Manual Produced May 2008 ...
Страница 3: ...iv ...
Страница 17: ...About this Manual xviii ...
Страница 28: ...9 Specifications Section 1 4 1 4 3 Dimensions 12 23 1 25 1 61 2 69 7 58 3 8 4 3 mm ...
Страница 29: ...10 Specifications Section 1 4 ...
Страница 39: ...20 Switches Section 2 3 ...
Страница 47: ...28 Installing the Turnback Units Section 3 2 ...
Страница 99: ...80 Last Maintenance Date Section 6 12 ...
Страница 113: ...94 Performance of Message Communications Section 8 2 ...
Страница 127: ...108 Other Error Causes and Error Procedures Section 9 3 ...
Страница 141: ...122 Power Consumption and Weight Tables Appendix D ...
Страница 143: ...124 Total I O Current Consumption Table Appendix E ...
Страница 147: ...128 Index ...
Страница 149: ...130 Revision History ...