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8 Sysmac Studio
GRT1-series EtherCAT Communication Unit - Operation Manual
8-3
Calcula
ting
I/O Refresh
T
ime
8
8-3
-2 Calculation I/O Refr
esh T
ime
5.
Calculate IO data size
The IO data size (
IO_size
in bytes) is defined as the maximum of the input data size (
IN_SIZE
)
and the output data size (
OUT_size
)
6.
Calculate I/O refresh time.
I/O refresh time =
Pack
+
Unpack
+
Xmit
Required are the calculations of OUT_size, IN_size and IO_size.
• Pack
Pack is the time required by the EtherCAT master to generate the OUT data.
Pack
= 0.007 *
OUT_size
(byte)
• Unpack
Unpack is time required by the EtherCAT master to retrieve the IN data.
Unpack
= 0.009 *
IN_size
(byte)
• Xmit
Xmit is the time required to transmit the EtherCAT data
Xmit
= Processing time per slave + transfer time per byte
Xmit
= 1.24 + 0.082 *
IO_size
(byte)
Calculate the IO_size
Calculate the I/O refresh time
Summary of Contents for GRT1-ECT SmartSlice
Page 3: ...GRT1 series EtherCAT Communication Unit Operation Manual Revised March 2012 ...
Page 18: ...15 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 30: ...1 EtherCAT Network 1 8 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 38: ...2 EtherCAT Communication details 2 8 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 52: ...4 GRT1 ECT Details 4 10 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 76: ...6 GRT1 ECT Troubleshooting 6 12 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 136: ...A4 Appendix Object Dictionary A4 16 GRT1 series EtherCAT Communication Unit Operation Manual ...
Page 140: ...Revision 2 GRT1 ECT series EtherCAT Slave Unit User s Manual ...