7 SSI Input Units
7 - 30
NX-series Position Interface Units User’s Manual (W524)
7-7 I/O Data Specifications
This section describes the data items that you can allocate to I/O, the data configurations, and the axis
settings.
You can assign the following 7 data items to the I/O for an SSI Input Unit.
The data items are described in the following sections.
You can use the Read NX Unit Object instruction or the Write NX Unit Object instruction to
access data that is not assigned as I/O. You use index numbers with these instructions.
Refer to the NJ/NX-series Instructions Reference Manual (Cat. No. W502) for information on
the Read NX Unit Object instruction or the Write NX Unit Object instruction.
For the index numbers, refer to A-2-3 SSI Input Units on page A-43.
The data items that you can allocate to I/O for a One-input Unit are listed in the following table.
7-7-1 Data Items for Allocation to I/O
NX-ECS112
Area Data item
Size
(bytes)
Data type
Default
*1
*1. The Default column shows the data item that are set when the Unit is shipped from the factory. You can allocate
other data items.
MC Function
Module PDO
*2
*2. These PDOs are required to use the MC Function Module.
Input SSI Status 1 BYTE Yes
SSI Communications Error Code 1 BYTE Yes
Encoder Present Position 4 DINT Yes Yes
Status Data 4 DWORD Yes
Encoder Present Position Refresh
Count
2UINT
Time Stamp
*3
*3. An EtherCAT Coupler Unit with unit version 1.1 or later is required.
8ULINT
Output SSI Operation Command 2 WORD