Device Configuration Format (Dcf) Records; Introduction; Dcf Clients - STMicroelectronics SPC572L series Reference Manual

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Device Configuration Format (DCF) Records

8.1

Introduction

Device Configuration Format (DCF) records are used to configure certain registers in the
device during system boot while the reset signal is asserted. An individual DCF record
consists of a pointer to the location of a register internal to the device and the respective
data.
There are two broad categories of DCF records:
•
TEST DCF records are developed by the factory. They can be used to write any DCF
client, but are used mainly to:
–
–
–
–
Note: The TEST DCF Records are programmed into TEST flash during production and cannot be
modified. TEST flash is not visible to the user.
•
UTEST DCF records can be either:
–
–
System boot is a complex process requiring a considerable amount of initialization to take
place before releasing reset. Before the device can be used in an application, the user
application code, reset vectors for all of the CPUs and the DCF records must be properly
programmed into their respective flash memories.
When power is applied to a properly programmed device:
1. The Power Management Controller (PMC) takes control of the device until the system
power supplies have reached predefined levels.
2. The PMC then signals the Reset Generation Module (RGM) to begin the boot
sequence.
3. During boot, the RGM enables the System Status and Control Module (SSCM) to read
the device configuration records and write information to specific registers.
8.2

DCF clients

DCF clients are 32-bit hardware registers inside a module that receive and store the data
from a DCF record. This stored data is used to initialize registers and to configure features.
DCF Clients have a default value before any DCF Records are written and may have
special writing constraints like 'Write Once' or only allowing bits to be written from '1' to '0' or
vice versa. DCF clients need not implement all 32 bits. DCF clients may be designated
Program registers involved in trimming trip points for voltage comparators.
Adjusting analog to digital voltage supplies.
Trim oscillator frequencies.
Enable RAM repair.
Factory programmed during production testing (see "UTEST flash memory map"
table in Chapter 5: Memory
User programmed when application code is written into the flash memory. User-
supplied UTEST DCF records start at the next location in the UTEST memory map
following the factory UTEST DCF records. The user-defined DCF records set up
the initial memory map, assign memory blocks as OTP and assign flash blocks to
be associated with specific password groups.
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Device Configuration Format (DCF) Records
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