Does STM32L151 has that option?
If does, where can I find a document about it? like AN3078 for I2C.
You can create IAP over any interface, using any protocol you choose.
For SPI you could emulate a FLASH or EEPROM type device.
For that matter you could just use SPI as a bidirectional serial interface, streaming data in X/Y-MODEM form.
Has ST published an example for SPI? I found only for I2C, USART and SD card.
There were examples of using the SPI System Boot Loader.
The presumption would be that your application already uses the SPI, so you'd have some familiarity with using it, and that the transport is a trivial part of the IAP implementation.
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