Bootloader Exit State - NXP Semiconductors MKL27Z128VFM4 Reference Manual

Table of Contents

Functional Description

Data Phase: The ReadMemory command has a data phase. Since the target (Kinetis

Bootloader) works in slave mode, the host need pull data packets until the number of

bytes of data specified in the byteCount parameter of ReadMemory command are

received by host.

Response: The target (Kinetis Bootloader) will return a GenericResponse packet with a

status code either set to kStatus_Success upon successful execution of the command, or

set to an appropriate error status code.

13.3.9 Bootloader Exit state

The Kinetis Bootloader tries to reconfigure the system back to the reset state in the

following situations:

• After completion of an Execute command, but before jumping to the specified entry

• After a peripheral detection timeout, but before jumping to the application entry

In general, all peripherals are reset. However, the application must consider the following

• I2C and SPI are restored by writing the control registers to reset values.

• LPUART is not restored.

• Peripheral pin mux is not reset to default, see the pin mux table (Kinetis Bootloader

Peripheral Pinmux).

Additional considerations:

• If VLPR mode is active during a system boot, then the bootloader will exit VLPR

mode on entry (to bootloader operation), and VLPR mode will not be restored after

exiting from the bootloader.

• If high speed clocking is selected in the Bootloader Configuration Area, then high

speed clocks will be retained after exiting from the bootloader.

• Upon exit from the bootloader, the bootloader leaves global interrupts disabled and

restores the VTOR register to its default value (0x0).

PORT clock gate, pin mux and peripheral registers are not reset

to default values on bootloader exit.

• Affected PORT clock gates: PORTA, PORTB, PORTC,

PORTD and PORTE(SIM_SCGC5_PORTA,

SIM_SCGC5_PORTB, SIM_SCGC5_PORTC,

SIM_SCGC5_PORTD and SIM_SCGC5_PORTE are

KL27 Sub-Family Reference Manual , Rev. 5, 01/2016

Freescale Semiconductor, Inc.