Function generator module "functiongenerator"

Description

THE "functiongenerator" MODULE IS MERELY A TEST MODULE FOR INTERNAL PURPOSES!

It is used for the temporally correct production of channel data.

Production here is based on complete data blocks.

Interfaces & protocols used

NONE

JSON configuration

The following section describes the entire JSON configuration of the module and explains the individual parameters.

Example configuration (typical configuration)

{
  "module": "FunctionGenerator",
  "factory": "functiongenerator",
  "config":{
    "maximumProductionCount":-1,
    "maximumTimestampDeviation":-1,
    "rtPriority":80,
    "samplesPerBlock":1,
    "timeoutSeconds":1,
    "timeoutNanoseconds":0,
    "startDate":"1970-01-01T00:00:00Z",
    "channels":[
      {
        "name": "Some Sine Channel",
        "dataType": "float",
        "bufferSize":1024,
        "function": "sine",
        "amplitude":1.0,
        "offset":0.0,
        "frequency":1.0,
        "onOffRatio":0.5
      },
      {
        "name": "Some Message Channel",
        "dataType": "string",
        "function": "messages",
        "messages":[
          {
            "timestamp":"1970-01-01T00:00:05Z",
            "text": "Hello, "
          },
          {
            "timestamp":"1970-01-01T00:00:10Z",
            "text": "World!"
          }
        ]
      },
      {
        "name": "Some Data Points",
        "dataType": "int32",
        "function": "datapoints",
        "datapoints":[
          {
            "timestamp":"1970-01-01T00:00:01Z",
            "value":42
          },
          {
            "timestamp":"1970-01-01T00:00:02Z",
            "value":24
          }
        ]
      },
      {
        "name": "Some Gps Locations",
        "dataType": "gpslocation",
        "function": "gpslocations",
        "gpslocations":[
          {
            "timestamp":"1970-01-01T00:00:01Z",
            "latitude":60.1234567,
            "longitude":15.7654321,
            "altitude":123.4
          },
          {
            "timestamp":"1970-01-01T00:00:02Z",
            "latitude":61.1234567,
            "longitude":16.7654321,
            "altitude":234.5
          }
        ]
      }
    ]
  }
}

Global module parameters

Parameter name	Required	Data type	Meaningful value range	Default	Description
maximumProductionCount	No	INT	-1, 1 -	-1	Maximum number of produced samples (-1 - infinite)
maximumTimestampDeviation	No	INT	-1, 1 -	-1	Maximum timestamp deviation [ns] from which the current smartCORE timestamp is used as the new starting point for the production of contiguous blocks (-1 - the start time is ALWAYS used as the time base)
rtPriority	No	INT	20 - 80	80	Priority of the production thread
bufferSize	No	INT	1 -	1024	Global buffer size of samples for all channels
samplesPerBlock	No	INT	1 -	1	Number of samples produced within a block
timeoutSeconds	No	INT	1 -	1	Production clock (specification of seconds)
timeoutNanoseconds	No	INT	1 -	0	Production clock (specification of nanoseconds)
startDate	No	STRING	UTC Zulu String or "now"	"now"	Production start time. For reproducible results and in the context of "messages", "datapoints" and "gpslocations", a constant specification as a UTC Zulu string is appropriate, while "now" specifies the current smartCORE timestamp as the start time.
channels	JA	JSON Array of JSON Objects			see below

Configuration of a channel (JSON object within "channels")

Parameter name	Required	Data type	Meaningful value range	Default	Description
name	YES	STRING			name of the channel
dataType	YES	STRING	see below		data type of the channel
bufferSize	No	INT	1 -	global "bufferSize" of the module	buffer size of the created channel
function	YES	STRING	see below		function to be produced
...					additional parameters (see below)

Supported channel data types 'dataType'

Note: Not all data types can be used in combination with all function specifications "function".

string (UTF-8 encoded)
bytearray
double
float
int64, int32, int16, int8
uint64, uint32, uint16, uint8
bool
gpslocation

Supported functions 'function'

linear
sine
sawtooth
triangle
rectangle
messages
datapoints
gpslocations

Mathematical functions

The following functions represent mathematical functions

linear
sine
sawtooth
triangle
rectangle

They have the following parameters in common

Parameter Name	Required	Data Type	Meaningful Value Range	Default	Description
amplitude	No	FLOAT	- 0.0 -	1.0	The amplitude (or multiplicative scaling) of the function
offset	No	FLOAT	- 0.0 -	0.0	The additive offset of the function
frequency	No	FLOAT	0.0 -	1.0	The frequency of the function [Hz]
onOffRatio	No	FLOAT	-1.0 - 1.0	0.5	The ratio between the on and off state of a rectangular function within a period; if the value is negative, the function is switched off at the start of a period

Function for the production of messages

This function can generally be used to produce several specified string or byte array messages. For this purpose, it is advisable to specify the global parameter "startDate" as a UTC Zulu string and thus an absolute time base, as the production times of the messages are also specified in absolute terms.

A single JSON array "messages" of JSON objects is specified, these objects are parameterized as follows:

Parameter Name	Required	Data Type	Meaningful Value Range	Default	Description
timestamp	YES	STRING	Zulu UTC String		Absolute production time
text	JA	STRING			Text of the message (always UTF-8 encoded)

Function for the production of discrete data points 'datapoints'

This function can generally be used to produce several specified data points (samples) of SCALARER and DATA TYPES SHOWABLE IN JSON. For this purpose, it is advisable to specify the global parameter "startDate" as a UTC Zulu string and thus an absolute time base, as the production times of the data points are also specified in absolute terms.

A single JSON array "datapoints" of JSON objects is specified, these objects are parameterized as follows:

Parameter Name	Required	Data Type	Meaningful Value Range	Default	Description
timestamp	YES	STRING	Zulu UTC String		Absolute production time
value	YES	...			Value of the data point represented in JSON

Function for the production of 3D GPS locations 'gpslocations'

This function can usually be used to produce several specified GPS locations. For this purpose, it is advisable to specify the global parameter "startDate" as a UTC Zulu string and thus an absolute time base, as the production times of the GPS locations are also specified in absolute terms.

A single JSON array "gpslocations" of JSON objects is specified, these objects are parameterized as follows:

Parameter name	Required	Data type	Meaningful value range	Description
timestamp	YES	STRING	Zulu UTC String	Absolute production time
latitude	JA	FLOAT		latitude
longitude	JA	FLOAT		longitude
altitude	JA	FLOAT		geographic altitude

Module information

Information	Value
Authors	optiMEAS Measurement and Automation Systems GmbH
since smartCORE	0.1
Module type	Producer
Dependencies	NONE

Description​

Interfaces & protocols used​

JSON configuration​

Example configuration (typical configuration)​

Global module parameters​

Configuration of a channel (JSON object within "channels")​

Supported channel data types 'dataType'​

Supported functions 'function'​

Mathematical functions​

Function for the production of messages​

Function for the production of discrete data points 'datapoints'​

Function for the production of 3D GPS locations 'gpslocations'​

Module information​