In the Analog tab, enter the digital signals to be acquired for the "Sniffer" module one after the other.

The individual columns in the signal list have the following meanings:

Name

Here, you can enter a signal name and additionally two comments when clicking the symbol in the Name field.

Unit

Here, you can enter the physical unit of the analog value.

Gain / Offset

Gradient (Gain) and y axis intercept (Offset) of a linear equation. You can convert a standardized and unitless transmitted value into a physical value.

Example: For a SIMATIC ET200 AI/AO module, a +/-10  V signal with a value range of -27648 … 27648 (equals -10 V … +10 V) is transferred. Within the control program, the transferred value has a physical meaning (e. g. temperature 50°C … 500°C). You can choose by Gain/Offset a conversion of the value. The value which has been acquired without a unit is then recorded with the physical unit.

For making the calculation of Gain/Offset easier, an auxiliary dialog appears when clicking on the co-ordinate cross icon in the Gain or Offset field. In this dialog, you only enter two points in the line equation. Gain and Offset are then calculated automatically.

Slave

Enter the slave address that is assigned to the signal. Here, you can enter third party slaves that are present on the bus line as well as own active slaves on the device.

I/O

Select the I/O type of the signal:

• In: Input signal from the master´s perspective

• Out: Output signal from the master´s perspective

• Service: Only for service purposes in support cases

Address

The byte address of the signal within the input or output data range of the slave. The address range always begins with the address 0.

Data type

Data type of the signal. Available data types:

Data type		Description	Value range
Big Endian	Little Endian	8 bit without plus/minus sign	0 to 255
BYTE	BYTE
INT_B	INT	16 bit with plus minus sign	-32768 to 32767
WORD_B	WORD	16 bit without plus/minus sign	0 to 65535
DINT_B	DINT	32 bit with plus minus sign	-2147483647 to 2147483647
DWORD_B	DWORD	32 bit without plus/minus sign	0 to 4294967295
FLOAT_B	FLOAT	IEEE754; Single Precision; 32 bit floating point	±3,402823 E+38 ... ±1,175495 E-38
S5_FLOAT_B	S5_FLOAT	Simatic S5 Float Format, 32 bit	±0,1701412 E+39 ... ±0,1469368 E-38

Tip

When entering the signals of a slave in sequential order, only the data types have to be selected for all signals. The byte addresses of the signals are then calculated automatically. For this purpose, please enter only for the first signal of the desired slave the correct byte address into the address column and then click on the column header. Starting with the first address (where the cursor is positioned) and considering all data types, the addresses of the other signals of this slave are filled in automatically.

Active

Only when this option is selected, the signal is acquired and considered when checking the number of licensed signals.

More columns can be displayed or hidden, using the context menu (right mouse-click on the header).