Siemens 500 NIM - Manual (Page 70)

NIM Primitives 4-17 SIMATIC TIWAY I Series 500 NIM User Manual
TT = 6, 7, 8 = Packed discrete (1 byte)
1 2 3 4 5 6 7 8
MSB LSB
Next sequential discrete bit accessed.
First discrete bit number accessed.
Value Bit Definition
0
1
Off
On
If the number of packed discrete bits requested is not an even multiple of eight,
the unused positions are set to zero.
Figure 4-5 Packed Discrete Data Element Format
TT = B = Word force (3 bytes)
MM <DDDD>
MM value Force state
00 Unforced
Forced 01
Note: An MM value of FF during a write operation 16
will unforce a point. Also, this MM value will not have
a DDDD field.
Figure 4-6 Forced Word Data Element Format