Omron GRT1-ECT SmartSlice, Руководство по эксплуатации

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8 Sysmac Studio
8 - 18 GRT1-series EtherCAT Communication Unit - Operation Manual
Please refer to the following example.
1.
Define the SmartSlice configuration
In this example:
GRT1-ID4 + GRT1-ID4 + GRT1-ID4 + GRT1-OD4 + GRT1-OD4 + GRT1-OD8 + GRT1-DA2V +
GRT1-AD2
2.
Calculate input Add all digital indata size
• puts together
ID4 (4 bits) + ID4 (4 bits) + ID4 (4 bits) = 12 bits
•
Divide the total number of digital inputs by 8 and round to the next integer value.
12 bits / 8 = 1.5, resulting in 2 bytes of digital input data
• Add the analog input data, 4 bytes per analog SmartSlice Input Unit
2 bytes (digital) + 4 bytes (analog) = 6 bytes
• Add 2 bytes for the Communication Unit status
6 bytes (d analog) + 2 bytes (Communication Unit status) = 8 bytes
• So IN_size = 8
3.
Calculate output data size
• Add all digital outputs together
OD4 (4 bits) + OD4 (4 bits) + OD4 (8 bits) = 16 bits
•
Divide the total number of digital outputs by 8 and round to the next integer value.
16 bits / 8 = 2 bytes of digital output data
• Add the analog output data, 4 bytes per analog SmartSlice Input Unit
2 bytes (digital) + 4 bytes (analog) = 6 bytes
• So OUT_size = 6
4.
Calculate IO data size
IN_size (8) > OUT_size (6), resulting in IO_size = 8
5.
Calculate I/O refresh time
Pack = 0.007 * OUT_size = 0.007 * 6 = 0.042
Unpack = 0.009 * IN_size = 0.009 * 8 = 0.072
Xmit = 1.24 + 0.082 * IO_size = 1.24 + 0.082 * 8 = 1.896
I/O refresh time per slave = Pack + Unpack + Xmit = 0.042 + 0.072 + 1.896 = 2.0us
8-3-3 Example calculation I/O refresh time