Siemens SINUMERIK Series

A4: Digital and analog NCK I/Os for SINUMERIK 840D sl
1.2 Access via PLC
Extended Functions
44 Function Manual, 03/2013, 6FC5397-1BP40-3BA1
Representation of the maximum value for different resolutions
Bit number 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Significance of the bits SG 2
14
2
13
2
12
2
11
2
10
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
16-bit resolution: 32767
D
= 7FFF
H
0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
14-bit resolution: 8191
D
= 1FFF
H
0 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0
12-bit resolution: 2047
D
= 7FF
H
0 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0
Note
The data (resolution, nominal range) of the analog input/output module used can be taken
from the documentation of the particular module.
Examples
Digital representation of analog values at a resolution of 14 bits including sign and a nominal
range of ±10 V.
Example 1: Analog value = 9.5 V
Digitized analog value (decimal): 9.5 V / 20 V * 16384 = 7782
Digitized analog value 14-bit (binary):
01 1110 0110 0110
Digitized analog value 16-bit (binary):
0111 1001 1001 1000
Digitized analog value 16-bit (hex): 7998
H
Example 2: Analog value = -4.12 V
Digitized analog value (decimal): -4.12 V / 20 V * 16384 = -3375
Digitized analog value 14-bit (binary):
11 0010 1101 0001
Digitized analog value 16-bit (binary):
1100 1011 0100 0100
Digitized analog value 16-bit (hex): CB44
H