Rxpdo And Txpdo Objects; Table 35: Generic Structure Of Rx/Txpdo (0X16Xx/0X1Axx) - WAGO I/O-SYSTEM 750 Manual

76 Function Description
7.3.1.5

RxPDO and TxPDO Objects

Both an RxPDO and a TxPDO are reserved for each I/O module.
The indices for the RxPDO's are assigned to the I/O modules by the modular
device profile using the following formula:
Index = 0x1600 + (number of the I/O module - 1)
If an I/O module does not have input or output data, then the corresponding Rx
and/or TxPDO does not exist.
The indices for the TxPDO's are assigned to the I/O modules by the modular
device profile using the following formula:
Index = 0x1A00 + (number of the I/O module - 1)
The Rx and/or TxPDO of a I/O module references in each case all entries in the
objects 0x6000 and/or 0x7000 in the I/O module. If an I/O module has dummy
bytes for word alignment, then these empty bits are likewise entered in the PDO
by referencing object 0x000:00.
RxPDO 0x16FF references the control data for the fieldbus coupler (0xF200).
TxPDO 0x1AFF references the status data of the fieldbus coupler (0xF100).
PDO's 0x1701 and 0x1B01 are used as necessary for inserting empty bits at the
end of the cyclically exchanged process data. They fill up the last 16 bit word
broken up by the digital I/O modules.
The following table presents the generic structure of a Rx/TxPDO.

Table 35: Generic Structure of Rx/TxPDO (0x16xx/0x1Axx)

Sub-Index Data Type
0
1...n
PDO Groups
Each PDO is assigned to a PDO group. The grouping is only relevant for offline
configuration.
• PDO Group 0: PDO's for the fieldbus coupler
• PDO Group 1: PDO's for complex I/O modules
• PDO Group 2: PDO's for digital I/O modules
Manual
Version 1.2.1
750-354/000-001 EtherCAT® Fieldbus Coupler, ID Switch
UINT8
UINT32
Number of bits
8
32
WAGO-I/O-SYSTEM 750
Description
Number of Entries
0xAAAABBCC
A: Index of the
referenced Objects
B: Subindex of the
referenced Objects
C: Number of referenced
Bits