Why on STM32CUBEF1 code version 1.8.1 bit FLASH_ACR_PRFTBE is not define? while on previous version on 3.5.0 it was defined.

[STiwa.1]

STM32F1_3.5.0 has bit description of FLASH_ACR_PRFTBE

STM32CUBEF1_1.8.1 has no bit description of FLASH_ACR_PRFTBE

[TDK]

It's still "used" in stm32f1xx_hal_flash.h, so probably a bug if not defined:

https://github.com/STMicroelectronics/STM32CubeF1/blob/441b2cbdc25aa50437a59c4bffe22b88e78942c9/Drivers/STM32F1xx_HAL_Driver/Inc/stm32f1xx_hal_flash.h#L231

/**
 * @brief Enable the FLASH prefetch buffer.
 * @retval None
 */ 
#define __HAL_FLASH_PREFETCH_BUFFER_ENABLE() (FLASH->ACR |= FLASH_ACR_PRFTBE)
 
/**
 * @brief Disable the FLASH prefetch buffer.
 * @retval None
 */
#define __HAL_FLASH_PREFETCH_BUFFER_DISABLE() (FLASH->ACR &= (~FLASH_ACR_PRFTBE))

[STiwa.1]

Thanks.

I read manual and got to know only flash half cycle access can be control rest bits are reserved.