Add SPI C++ HAL Wrapper Layer

[shibcreate]

Description:

Introduce a modern C++ wrapper for the STM32 HAL SPI peripheral.

The goal is not to reimplement SPI from scratch, but to wrap HAL APIs in a C++ abstraction that improves usability, readability, and maintainability for application-level code.

Proposed Scope:

• Class-based SPI interface
• Constructor-based initialization
• Chip-select handling
• Minimal overhead; no dynamic allocation

Acceptance Criteria:

• Compiles cleanly on at least one supported Nucleo board
• Uses STM32 HAL internally (no direct register access)
• Clear public API with header/source separation
• Keep interface simple and extensible for future DMA/IRQ support

[shibcreate]

@MootSeeker, I will be looking into this issue in the coming weeks. Currently looking into how to test the SPI protocol, since I would need a logic analyzer to ensure my SPI communication works. Do you recommend me testing this way or connect the SPI between two nucleo boards to test basic loopback communication?

[MootSeeker]

@MootSeeker, I will be looking into this issue in the coming weeks. Currently looking into how to test the SPI protocol, since I would need a logic analyzer to ensure my SPI communication works. Do you recommend me testing this way or connect the SPI between two nucleo boards to test basic loopback communication?

@shibcreate That's a solid plan, as having a logic analyzer is definitely the gold standard for verifying signal integrity and timing. However, rather than setting up a loopback between two Nucleo boards, which requires you to manage the logic for both a master and a slave simultaneously. I would highly recommend testing your SPI communication against an external Flash or EEPROM chip. Using a dedicated memory chip is often much more efficient because these components follow a predictable, industry-standard protocol. By simply attempting to read the JEDEC ID or writing a byte and reading it back, you can immediately verify if your configuration is correct.
If you get the expected manufacturer ID back, you know your physical wiring, clock polarity, and phase are all spot on.

[shibcreate]

Thank you for your feedback! That sounds good. I will purchase a small flash/eeprom chip to test communications.

[MootSeeker]

@shibcreate Any updates on this?