NIM Primitives
4-14 SIMATIC TIWAY I Series 500 NIM User Manual
4.6 Data Element Types and Formats

The data element types (TTs) and their length (in bytes) are defined in

Table 4-4. Figure 4-4 through Figure 4-15 show the format of the data

elements.

Table 4-4 Data Element Types and Formats

TT Data Element Type Length
(in bytes)
0Instruction Memory (L) 2
1Variable Memory (V) 2
2Constant Memory (K) 2
3Discrete Input (X) 1
4Discrete Output (Y) 1
5Control Register (CR) 1
6Discrete Input Packed (X) 1
7Discrete Output Packed (Y) 1
8Control Register Packed (CR) 1
9Word Input (WX) 2
AWord Output (WY) 2
BXY Force 1
CCR Force 1
DWord Force 3
ETimer-Counter Preset (TCP) 2
FTimer-Counter Current (TCC) 2
10 Drum Step Preset (DSP) 1
11 Drum Step Current (DSC) 1
12 Drum Count Preset (DCP) 2
17 Secondary System Status* 4
** 20 or 60 Loop Gain 4
** 21 or 61 Loop Reset 4
** 22 or 62 Loop Rate 4
** 23 or 63 Loop High Alarm 4
** 24 or 64 Loop Low Alarm 4
** 25 or 65 Loop Process Variable 4
* These TT types are read-only data elements.
# This TT type is a write-only data element.
** Format
2x, 3x, and 4x = IBM format
6x, 7x, and 8x = IEEE format