Introduction
This programming manual describes how to program the Flash memory of STM32W108 microcontrollers for the wireless line.
The STM32Wxxx embedded Flash memory can be programmed using in-circuit programming or in-application programming.

The in-circuit programming (ICP) method is used to update the entire contents of the Flash memory, using the JTAG, SWD protocol or the boot loader to load the user application into the microcontroller. ICP offers quick and efficient design iterations and eliminates unnecessary package handling or socketing of devices.

In contrast to the ICP method, in-application programming (IAP) can use any communication interface supported by the microcontroller (I/Os, USB, CAN, UART, I2C, SPI, etc.) to download programming data into memory. IAP allows the user to re-program the Flash memory while the application is running. Nevertheless, part of the application has to have been previously programmed in the Flash memory using ICP.

The Flash interface implements instruction access and data access based on the AHB protocol. It implements a prefetch buffer that speeds up CPU code execution. It also implements the logic necessary to carry out Flash memory operations (Program/Erase). Program/Erase operations can be performed over the whole product voltage range. Read/Write protections and option bytes are also implemented.

FEATUREs
● 64 Kbytes, 128 Kbytes, 192 Kbytes or 256 Kbytes of Flash memory
● Memory organization:
   – Main Flash Block (MFB)
   – Fixed Information Block (FIB)
   – Customer Information Block (CIB)
   Flash memory interface (FLITF) features:
● Read interface with prefetch buffer (2 × 64-bit words)
● Option byte Loader
● Flash Program / Erase operation
● Read / Write protection
● Low-power mode