ACS_BOOT_CFG

Bit Field

Read/Write

Field Name

Description

8

RW

PADS_RETENTION_EN

Enable / Disable the retention mode of the pads

6

RW

BOOT_ROT_BYPASS

Boot bypass execution of root of trust

5

RW

BOOT_PWR_CAL_BYPASS

Boot bypass execution of system calibration

4:3

R

RC_CLOCK_FSEL

RC oscillator clock multiplier read only flag (mirror of CLOCK_MULT of ACS_RCOSC_CTRL register)

2

R

RC_FTRIM_FLAG

RC oscillator trimming read only flag (mirror of FTRIM_FLAG of ACS_RCOSC_CTRL register

1:0

RW

BOOT_SELECT

Boot selection to indicate boot source

Bit Field

Field Name

Value Symbol

Value Description

Hex Value

8

PADS_RETENTION_EN

PADS_RETENTION_DISABLE

Disable the pad retention mode

0x0*

PADS_RETENTION_ENABLE

Enable the pad retention mode

0x1

6

BOOT_ROT_BYPASS

BOOT_ROT_BYPASS_DISABLE

ROM will execute RoT

0x0*

BOOT_ROT_BYPASS_ENABLE

ROM will not execute RoT

0x1

5

BOOT_PWR_CAL_BYPASS

BOOT_PWR_CAL_BYPASS_DISABLE

ROM will execute calibration of system

0x0*

BOOT_PWR_CAL_BYPASS_ENABLE

ROM will not execute calibration of system

0x1

4:3

RC_CLOCK_FSEL

RC_OSC_STATUS_3MHZ

The RC Oscillator is at 3 MHz

0x0*

RC_OSC_STATUS_12MHZ

The RC Oscillator is at 12 MHz

0x1

RC_OSC_STATUS_24MHZ

The RC Oscillator is at 24 MHz

0x2

RC_OSC_STATUS_48MHZ

The RC Oscillator is at 48 MHz

0x3

2

RC_FTRIM_FLAG

RC_OSC_STATUS_UNCALIBRATED

The oscillators are not calibrated

0x0*

RC_OSC_STATUS_CALIBRATED

The oscillators are calibrated

0x1

1:0

BOOT_SELECT

BOOT_FLASH_XTAL_DISABLE

The CM33 executes code from the flash and the XTAL will not be started at boot

0x0*

BOOT_CUSTOM

The CM33 executes code from the address specified in the wakeup information in retention RAM and the XTAL will not be started at boot

0x1

BOOT_FLASH_XTAL_DEFAULT_TRIM

The CM33 executes code from the flash and the XTAL will be started at boot with the default trim

0x2

BOOT_FLASH_XTAL_CUSTOM_TRIM

The CM33 executes code from the flash and the XTAL will be started at boot with trim from ACS_WAKEUP_GP_DATA

0x3