MKMxxZxxACxx5 Bare Metal Software Drivers  R4.1.6
Reference Manual
Boot Modes

This section summarizes boot sequences supported by the MKM34Z128CLL5 device and ways of their entering by means of modifications performed in the appconfig.h file. Each particular boot mode is characteristic by a peak current, average current and duration of the power up cycle. These characteristics measured during power up cycle of the real device including transient responses of the RESET signal and IDD current are the following:


RUN Boot Fast Clock - Flash Clocked by 25 MHz During Initialization (default). Mode entered by all "BOOT_..." constants commented in the appconfig.h configuration file.

run1_boot.bmp
Supply Voltage Ramp Supply Voltage (V) Peak Current (mA) Mean Current (mA)Boot Time (ms) Boot Energy (Ws)
linear 1.7 ms settling time3.26 4.75 1.39 1.3 2.87e-6

RUN Boot Slow Clock - Flash Clocked by 25 MHz During Initialization. Mode entered by "BOOT_DIV_CLK_BY_8" constant left uncommented in the appconfig.h configuration file.

run2_boot.bmp
Supply Voltage Ramp Supply Voltage (V) Peak Current (mA) Mean Current (mA)Boot Time (ms) Boot Energy (Ws)
linear 1.7 ms settling time3.26 5.44 1.75 4.0 19.86e-6

RUN Boot Fast Clock - Flash Clocked by 1 MHz During Initialization. Mode entered by "BOOT_EXT_CLK" constant left uncommented in the appconfig.h configuration file.

run3_boot.bmp
Supply Voltage Ramp Supply Voltage (V) Peak Current (mA) Mean Current (mA)Boot Time (ms) Boot Energy (Ws)
linear 1.7 ms settling time3.26 3.18 1.67 2.4 9.36e-6

RUN Boot Fast Clock and Entering VLPR in SW - Flash Clocked by 1 MHz During Initialization. Mode entered by "BOOT_SWVLPR_MODE" and "BOOT_EXT_CLK" constant left uncommented in the appconfig.h configuration file.

run4_boot.bmp
Supply Voltage Ramp Supply Voltage (V) Peak Current (mA) Mean Current (mA)Boot Time (ms) Boot Energy (Ws)
linear 1.7 ms settling time3.26 3.40 1.70 2.5 10.06e-6

Very Low Power RUN Boot. Mode entered by "BOOT_HWVLPR_MODE" constant left uncommented in the appconfig.h configuration file.

vlpr_boot.bmp
Supply Voltage Ramp Supply Voltage (V) Peak Current (mA) Mean Current (mA)Boot Time (ms) Boot Energy (Ws)
linear 1.7 ms settling time3.26 2.33 1.39 4.1 16.06e-6

In order to handle current spikes during Flash charging and Flash NVOPT fetching (when booting in RUN mode), a capacitors on VDD supply pins are required. The capacitors on VDD supply pins shall deliver current up to 6.41 mA for short duration (5 us) without significant voltage drop.


Source code:
/******************************************************************************
* (c) Copyright 2010-2015, Freescale Semiconductor Inc.
* ALL RIGHTS RESERVED.
******************************************************************************
* bootpwr_test.c
******************************************************************************/
#include "drivers.h"
/* RESETB PIN definition */
#define PIN_RESETB PIN1 /* PTE1 */
void main (void)
{
PORT_Init (PORTE , PORT_MODULE_ALT1_MODE, PIN_RESETB);
GPIO_Init (FGPIOE, GPIO_OUT_LOGIC1_MODE , PIN_RESETB);
GPIO_Clr(FGPIOE, PIN_RESETB);
arch_delay (0x20);
GPIO_Set(FGPIOE, PIN_RESETB);
/* main programme loop */
while(1);
}
Appconfig.h:
/******************************************************************************
* (c) Copyright 2010, Freescale Semiconductor Inc.
* ALL RIGHTS RESERVED.
***************************************************************************/
#ifndef __APPCONFIG_H
#define __APPCONFIG_H
/***************************************************************************/
//#define MTB_RAM_RESERVE
/***************************************************************************/
#define BOOT_NMI_DISABLE
//#define BOOT_EXT_CLK
//#define BOOT_DIV_CLK_BY_8
//#define BOOT_HWVLPR_MODE
//#define BOOT_SWVLPR_MODE
/***************************************************************************/
/******************************************************************************/
#endif /* __APPCONFIG_ */