daisy::PersistentStorage¶

Non Volatile storage class for persistent settings on an external flash device. More...

#include <PersistentStorage.h>

Public Types¶

	Name
enum class	State

Public Functions¶

	Name
	PersistentStorage(QSPIHandle & qspi)
void	Init(const SettingStruct & defaults, uint32_t address_offset =0)
State	GetState() const
SettingStruct &	GetSettings()
void	Save()
void	RestoreDefaults()

Detailed Description¶

template <typename SettingStruct >
class daisy::PersistentStorage;

Non Volatile storage class for persistent settings on an external flash device.

Author: shensley

Todo:

Make Save() non-blocking
Add wear leveling

Storage occupied by the struct will be one word larger than the SettingStruct used. The extra word is used to store the state of the data, and whether it's been overwritten or not.

Public Types Documentation¶

enum State¶

Enumerator	Value	Description
UNKNOWN	0
FACTORY	1
USER	2

State of the storage. When created, prior to initialiation, the state will be Unknown

During initialization, the state will be changed to either FACTORY, or USER.

If this is the first time these settings are being written to the target address, the defaults will be written to that location, and the state will be set to FACTORY.

Once the first user-trigger save has been made, the state will be updated to USER to indicate that the defaults have overwritten.

Public Functions Documentation¶

function PersistentStorage¶

inline PersistentStorage(
    QSPIHandle & qspi
)

Parameters:

qspi reference to the hardware qspi peripheral.

Constructor for storage class

function Init¶

inline void Init(
    const SettingStruct & defaults,
    uint32_t address_offset =0
)

Parameters:

defaults should be a setting structure containing the default values. this will be updated to contain the stored data.
address_offset offset for location on the QSPI chip (offset to base address of device). This defaults to the first address on the chip, and will be masked to the nearest multiple of 256

Initialize Storage class

The values in this class will be stored as the default for restoration to 'factory' settings.

function GetState¶

inline State GetState() const

Returns the state of the Persistent Data

function GetSettings¶

inline SettingStruct & GetSettings()

Returns a reference to the setting struct

function Save¶

inline void Save()

Performs the save operation, storing the storage

function RestoreDefaults¶

inline void RestoreDefaults()

Restores the settings stored in the QSPI

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Updated on 2024-01-03 at 19:41:00 +0000