4
EtherCAT
®
Communication Protocol Manual
– p/n 20018109-001 Rev. B
Device Address Switches
The Device ID and the Configured Station Alias can be set by three hexadecimal rotary switches
(labeled “ID” in
Figure 1) as stated in ETG.5003.1 and ETG.1020.
𝐴𝑑𝑑𝑟𝑒𝑠𝑠 = 𝑥100(0𝑥100) + 𝑥10(0𝑥10) + 𝑥1(0𝑥1)
For example, if the address switches from MSD to LSD are set to “321” –
𝐴𝑑𝑑𝑟𝑒𝑠𝑠 = 3(0𝑥100) + 2(0𝑥10) + 3(0𝑥1) = 0𝑥321
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Device Profile
The 390 is a Vacuum Pressure Gauge (VPG) Combo Device (CG) conforming to ETG.5003.2080. Several
pressure sensors
are used to create “Combination” and “Differential” pressures. Each pressure sensor is its own
Module.
Table 4: Module to Sensor Mapping
Module Number
Pressure Sensor
0
Absolute Piezo
1
Differential Piezo
2
Conductron (Heat Transfer)
3
Hot Cathode Ion
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Process Data Objects
Fast information flow (polling rates up to 1ms according to ETG.5003.1) between Slave and the Master is ensured
by the use of PDOs. Important information (i.e. pressure
– see Poll Current Pressure) is mapped from the Object
Dictionary into PDO objects. Information about setting PDOs is found in Modifying PDO Mapping and ETG.1020.
Per ETG.5003.2080, each Module has its own set of PDOs.
Table 5: Module to PDO Mapping
Module Number
RxPDO Indexes
TxPDO Indexes
1
0x1600, 0x1601
0x1A00, 0x1A01
2
0x1602, 0x1603
0x1A02, 0x1A03
3
0x1604, 0x1605
0x1A04, 0x1A05
4
0x1606, 0x1607
0x1A06, 0x1A07
The device as a whole also has two sets of PDOs.
RxPDO Indexes
TxPDO Indexes
0x17FE, 0x17FF
0x1BFE, 0x1BFF
There are two default PDOs populated with information about the Differential Pressure and Combination
Pressure.
Table 6: Differential Sensor Default PDO
PDO Index
Sub
Index
PDO Entry
Index
PDO Sub
Index
Bit
Length
Name
