1. Generate and Download the SDK package for the targetted platform/MCU

2. Unpack the SDK into a temporary location $FREESCALE_KINETIS_ROOT

3. Copy $FREESCALE_KINETIS_ROOT/devices to $POLYMCU_ROOT/Device/Freescale
   Copy $FREESCALE_KINETIS_ROOT/middleware to $POLYMCU_ROOT/Device/Freescale

• SUPPORT_DEBUG_UART can be either uart, lpuart, lpsci
• BOARD_DEBUG_UART_INSTANCE defines which instance of the Debug UART devices to use.

You can reduce Kinetis KL27 footprint by defining empty IRQ Handlers for devices you are not using.
By default, Kinetis SDK adds all interrupt driver support that could make the size of the firmware larger.

For instance:

void UART2_FLEXIO_DriverIRQHandler(void) { }
void I2C0_DriverIRQHandler(void) { }
void I2C1_DriverIRQHandler(void) { }
void SPI0_DriverIRQHandler(void) { }
void SPI1_DriverIRQHandler(void) { }
void DMA0_DriverIRQHandler(void) { }
void DMA1_DriverIRQHandler(void) { }
void DMA2_DriverIRQHandler(void) { }
void DMA3_DriverIRQHandler(void) { }