#if defined(GEX_PLAT_F103_BLUEPILL)
    // Platform STM32F103C8T6 Bluepill ($4 board from eBay)

    // Units supported by the platform (known to work correctly)

    // free all present resources
    {
        rsc_free_range(NULL, R_ADC1, R_ADC2);
        rsc_free_range(NULL, R_I2C1, R_I2C2);
        rsc_free_range(NULL, R_SPI1, R_SPI2);
        rsc_free_range(NULL, R_TIM1, R_TIM4);
        rsc_free_range(NULL, R_USART1, R_USART3);
        rsc_free_range(NULL, R_PA0, R_PA15);
        rsc_free_range(NULL, R_PB0, R_PB15);
        rsc_free_range(NULL, R_PC13, R_PC15);
        rsc_free_range(NULL, R_PD0, R_PD1);
    }

    // Claim resources not available due to board layout or internal usage
    {
        // HAL timebase
        rv |= rsc_claim(&UNIT_SYSTEM, R_TIM1);
        // HSE crystal
        rv |= rsc_claim(&UNIT_SYSTEM, R_PD0);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PD1);
        // SWD
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA13);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA14);
        // USB
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA11);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA12);
        // BOOT pin(s)
        rv |= rsc_claim(&UNIT_SYSTEM, R_PB2); // BOOT1
    }
#elif defined(STM32F072xB)
    // Platform STM32F073RBT


    // Free all present resources
    {
        rsc_free(NULL, R_ADC1);
//        rsc_free(NULL, R_CAN1);
//        rsc_free_range(NULL, R_COMP1, R_COMP2);
        rsc_free(NULL, R_DAC1);
//        rsc_free(NULL, R_HDMI_CEC);
        rsc_free(NULL, R_TSC);
        rsc_free_range(NULL, R_I2C1, R_I2C2);
//        rsc_free_range(NULL, R_I2S1, R_I2S2);
        rsc_free_range(NULL, R_SPI1, R_SPI2);
        rsc_free_range(NULL, R_TIM1, R_TIM3);
        rsc_free_range(NULL, R_TIM6, R_TIM7);
        rsc_free_range(NULL, R_TIM14, R_TIM17);
        rsc_free_range(NULL, R_USART1, R_USART4);
        rsc_free_range(NULL, R_DMA1_1, R_DMA1_7);

        rsc_free_range(NULL, R_PA0, R_PA15);
        rsc_free_range(NULL, R_PB0, R_PB15);
        rsc_free_range(NULL, R_PC0, R_PC15);
        rsc_free(NULL, R_PD2);
        rsc_free_range(NULL, R_PF0, R_PF1);
    }

    // Claim resources not available due to board layout or internal usage
    {
        // HAL timebase
        rv |= rsc_claim(&UNIT_SYSTEM, R_TIM17);
        // HSE crystal
        rv |= rsc_claim(&UNIT_SYSTEM, R_PF0);

        #if PLAT_FULL_XTAL
            rv |= rsc_claim(&UNIT_SYSTEM, R_PF1); // - not used in BYPASS mode
        #endif

        // SWD
//        rv |= rsc_claim(&UNIT_SYSTEM, R_PA13);
//        rv |= rsc_claim(&UNIT_SYSTEM, R_PA14);
        // USB
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA11);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA12);

        #if defined(GEX_PLAT_F072_ZERO)
            // unconnected pins
            rv |= rsc_claim_range(&UNIT_PLATFORM, R_PC0, R_PC1);
            rv |= rsc_claim_range(&UNIT_PLATFORM, R_PC4, R_PC9);
        #endif
    }
#elif defined(GEX_PLAT_F303_DISCOVERY)
    // Platform STM32F303VCT

    // Additional GPIO ports
    __HAL_RCC_GPIOF_CLK_ENABLE();

    // Units supported by the platform (known to work correctly)
    // ureg_add_type(&UNIT_XYZ);

    // Free all present resources
    {
        rsc_free_range(NULL, R_ADC1, R_ADC4);
//        rsc_free(NULL, R_CAN1);
//        rsc_free_range(NULL, R_COMP1, R_COMP7);
//        rsc_free(NULL, R_HDMI_CEC);
        rsc_free(NULL, R_DAC1);
        rsc_free_range(NULL, R_I2C1, R_I2C2);
        rsc_free_range(NULL, R_I2S2, R_I2S3);
//        rsc_free_range(NULL, R_OPAMP1, R_OPAMP4);
        rsc_free_range(NULL, R_SPI1, R_SPI3);
        rsc_free_range(NULL, R_TIM1, R_TIM4);
        rsc_free_range(NULL, R_TIM6, R_TIM8);
        rsc_free_range(NULL, R_TIM15, R_TIM17);
        rsc_free(NULL, R_TSC);
        rsc_free_range(NULL, R_USART1, R_USART5);

        rsc_free_range(NULL, R_PA0, R_PA15);
        rsc_free_range(NULL, R_PB0, R_PB15);
        rsc_free_range(NULL, R_PC0, R_PC15);
        rsc_free_range(NULL, R_PD0, R_PD15);
        rsc_free_range(NULL, R_PE0, R_PE15);

        rsc_free_range(NULL, R_PF0, R_PF2);
        rsc_free(NULL, R_PF4);
        rsc_free_range(NULL, R_PF9, R_PF10);
    }

    // Claim resources not available due to board layout or internal usage
    {
        // HAL timebase
        rv |= rsc_claim(&UNIT_SYSTEM, R_TIM1);
        // HSE crystal
        rv |= rsc_claim(&UNIT_SYSTEM, R_PF0);
        //rv |= rsc_claim(&UNIT_SYSTEM, R_PF1); // - not used in BYPASS mode
        // SWD
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA13);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA14);
        // USB
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA11);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA12);
        // BOOT pin(s)
        rv |= rsc_claim(&UNIT_SYSTEM, R_PB2); // BOOT1
    }
#elif defined(GEX_PLAT_F407_DISCOVERY)
    // Platform STM32F407VGT

    // Additional GPIO ports
    __HAL_RCC_GPIOF_CLK_ENABLE();

    // Units supported by the platform (known to work correctly)
    // ureg_add_type(&UNIT_XYZ);

    // Free all present resources
    {
        rsc_free_range(NULL, R_ADC1, R_ADC3);
//        rsc_free_range(NULL, R_CAN1, R_CAN2);
//        rsc_free_range(NULL, R_COMP1, R_COMP7);
        rsc_free(NULL, R_DAC1);
//        rsc_free(NULL, R_DCMI);
//        rsc_free(NULL, R_ETH);
//        rsc_free(NULL, R_FSMC);
        rsc_free_range(NULL, R_I2C1, R_I2C3);
        rsc_free_range(NULL, R_I2S2, R_I2S3);
//        rsc_free(NULL, R_SDIO);
        rsc_free_range(NULL, R_SPI1, R_SPI3);
        rsc_free_range(NULL, R_TIM1, R_TIM14);
        rsc_free_range(NULL, R_USART1, R_USART3);
        rsc_free(NULL, R_USART6);

        rsc_free_range(NULL, R_PA0, R_PA15);
        rsc_free_range(NULL, R_PB0, R_PB15);
        rsc_free_range(NULL, R_PC0, R_PC15);
        rsc_free_range(NULL, R_PD0, R_PD15);
        rsc_free_range(NULL, R_PE0, R_PE15);
        // also has 2 PH pins

        // F407 appears to have fewer GPIOs than F303?
    }

    // Claim resources not available due to board layout or internal usage
    {
        // HAL timebase
        rv |= rsc_claim(&UNIT_SYSTEM, R_TIM1);
        // HSE crystal
        // H0 and H1
        // SWD
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA13);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA14);
        // USB
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA11);
        rv |= rsc_claim(&UNIT_SYSTEM, R_PA12);
        // BOOT pin(s)
        rv |= rsc_claim(&UNIT_SYSTEM, R_PB2); // BOOT1
    }
#else
    #error "BAD PLATFORM!"
#endif