writeAnything

Signatures

• template <class T> bool SPIFlash::writeAnything(uint32_t _addr, const T& data, bool errorCheck = true)
• template <class T> bool SPIFram::writeAnything(uint32_t _addr, const T& data, bool errorCheck = true)

What It Is For

Write any trivially copyable object (struct, packed config, fixed-size type) as raw bytes.

Parameters

• _addr: Start address.
• data: Object instance to serialize byte-for-byte.
• errorCheck: Enables optional verification after write.

Behavior Details

Storage format is raw in-memory layout. Compiler packing/alignment/type definitions must remain consistent between write and read firmware versions.

Return Semantics

Returns true on full write success.

Failure Behavior

Changing struct layout between firmware versions breaks compatibility unless you version and migrate your data format.

Common Mistakes

• Changing struct layout between firmware versions without migration.
• Using non-trivially-copyable types/pointers inside persisted structs.
• Forgetting erase-before-write requirement on flash.

Choosing Between Similar APIs

• Use writeAnything() for stable structs/config blobs.
• Use typed APIs (writeULong, writeFloat, etc.) for simple scalar values.
• Use byte/char array APIs when you need explicit binary format control.

Example

struct Config { uint16_t mode; float gain; } cfg{2, 1.25f};
flash.eraseSection(addr, sizeof(Config));
flash.writeAnything(addr, cfg);