Module: dataStorageUnitBase¶

Executive Summary¶

DataStorageUnitBase is a base class that is used generate a standard interface and list of features for modules that store simulated onboard data. This class is used by other modules as a parent class and cannot be instantiated by itself. All Basilisk data storage modules based on this DataStorageUnitBase inherit the following common properties:

Writes out a dataStorageStatusSimMsg containing the sum of the current stored data (in bits), the storage capacity (bits), the current net data rate (in baud), an array of char array containing the names of the stored data (ex. Instrument 1, Instrument 2), and an array of doubles containing the stored data associated with each type (bits).
Allows for multiple dataNodeUsageSimMsg corresponding to individual Module: dataNodeBase instances to be subscribed to using the addDataNodeToModel method.
Iterates through attached dataNodeUsageSimMsg instances, integrates the data for each data node, and adds it to its respective entry using integrateDataStatus() method, which may be overwritten in child classes.
Loops through the vector of storedData to sum the total amount of data contained within the storage unit.

Core functionality is wrapped in the integrateDataStatus protected virtual void method, which computes the amount of data stored in a storage unit on a module basis. This base class automatically implements a partitioned storage unit (different data buffers for each device). See Module: simpleStorageUnit for an example of how this functionality can be overwritten.

Protected methods prepended with custom are intended for module developers to override with additional, module-specific functionality.

For more information on how to set up and use classes derived from this module, see the simple data system example: scenarioDataDemo

Module Assumptions and Limitations¶

The base class makes no specific data storage device related assumptions.

Message Connection Descriptions¶

The following table lists all the module input and output messages. The module msg variable name is set by the user from python. The msg type contains a link to the message structure definition, while the description provides information on what this message is used for.

Module I/O Messages¶
Msg Variable Name	Msg Type	Description
nodeDataUseMsgNames	dataNodeUsageSimMsg	Input messages. Vector of data node usage messages. Set using `addDataNodeToModel`
storageUnitDataOutMsgName	dataStorageStatusSimMsg	Output message. Describes storage unit capacity, storage level, net data rate, and contents.

User Guide¶

The user must set the output message name variable storageUnitDataOutMsgName in Python.
The input message names (data nodes) are provided by calling the method addDataNodeToModel()

class DataStorageUnitBase : public SysModel ¶

Public Functions

DataStorageUnitBase()¶

This method initializes some basic parameters for the module.

Return: void

~DataStorageUnitBase()¶

Destructor.

Return: void

void SelfInit()¶

SelfInit for this class.

Return: void

void CrossInit()¶

CrossInit for this class. Subscribes to dataNodes that will send data to storage unit.

Return: void

void Reset(uint64_t CurrentSimNanos)¶

This method is used to reset the module.

Return

void

Parameters

CurrentSimNanos:

void addDataNodeToModel(std::string tmpNodeMsgName)¶

Adds dataNode to the storageUnit.

Adds a simDataNodeMsg name to be iterated over. Called in Python.

Return

void

Parameters

tmpNodeMsgName:

void UpdateState(uint64_t CurrentSimNanos)¶

Reads messages, adds new data to the storage unit, and writes out the storage unit status

Return

void

Parameters

CurrentSimNanos: The current simulation time in nanoseconds

std::vector<dataInstance> getStoredDataAll()¶

Getter function for the storedData vector.

Getter function for all of the stored data

Return: std::vector<dataInstance>

double getStoredDataSum()¶

Getter function for the storedDataSum.

Getter function for sum of the stored data

Return: double

Public Members

std::vector<std::string> nodeDataUseMsgNames¶: Vector of data node input message names.

std::string storageUnitDataOutMsgName¶: Vector of message names to be written out by the storage unit.

double storageCapacity¶

BSKLogger bskLogger¶: Storage capacity of the storage unit.

Protected Functions

void writeMessages(uint64_t CurrentClock)¶

Loops through the storedData vector and assigns values to output message.

Return

void

Parameters

CurrentClock: The current time used for time-stamping the message

bool readMessages()¶

This method is used to read the incoming data supply/outgoing data messages and store them for future use.

Return: void

void integrateDataStatus(double currentTime)¶

Integrates the dataStatus over all of the dataNodes.

Loops through all of the input messages, integrates the baud rates, and adds the new data to the storedData vector

Return

void

Parameters

currentTime:

void customSelfInit()¶

void customCrossInit()¶: Custom output input reading method. This allows a child class to add additional functionality.

void customReset(uint64_t CurrentClock)¶: Custom subscription method, similar to customSelfInit.

void customWriteMessages(uint64_t CurrentClock)¶: Custom Reset method, similar to customSelfInit.

bool customReadMessages()¶: custom Write method, similar to customSelfInit.

int messageInStoredData(DataNodeUsageSimMsg *tmpNodeMsg)¶

Custom read method, similar to customSelfInit; returns true by default.

Returns index of the dataName if it’s already in storedData

Checks to see if a data node is in the storedData vector or not, returns the index.

Return

index

Parameters

tmpNodeMsg:

double sumAllData()¶

Sums all of the data in the storedData vector.

Sums all of the data in the storedData vector

Return: double

Protected Attributes

std::vector<std::int64_t> nodeDataUseMsgIds¶: Vector of all the data node messages IDs the storage unit is subscribed to.

int64_t storageUnitDataOutMsgId¶: Message ID of storage Unit output message.

DataStorageStatusSimMsg storageStatusMsg¶

std::vector<DataNodeUsageSimMsg> nodeBaudMsgs¶

double storedDataSum¶: [bits] Stored data in bits.

std::vector<dataInstance> storedData¶

double previousTime¶: Vector of data. Represents the makeup of the data buffer.

double currentTimestep¶: Previous time used for integration.

double netBaud¶: [s] Timestep duration in seconds.

uint64_t outputBufferCount¶: Net baud rate at a given time step.