SC9RS08KA2 datasheet(32/134 Pages) FREESCALE

32 / 134 page

Chapter 4 Memory

SC9RS08KA2 Series Data Sheet, Rev. 1

Freescale Semiconductor

NOTE

When the device boots up to normal operating mode, where MS pin is high

during reset, with SECD programmed (SECD = 0), Flash security is

engaged. BKGDPE is reset to 0, and all BDM communication is blocked,

and background debug is not allowed.

4.7

Flash Registers and Control Bits

The Flash module has a nonvolatile register, NVOPT ($3FFC), in Flash memory which is copied into the

corresponding control register, FOPT ($0210), at reset.

4.7.1

Flash Options Register (FOPT and NVOPT)

During reset, the contents of the nonvolatile location NVOPT is copied from Flash into FOPT. Bits 7

through 1 are not used and always read 0. This register may be read at any time, but writes have no meaning

or effect. To change the value in this register, erase and reprogram the NVOPT location in Flash memory

as usual and then issue a new MCU reset.

765

432

000

SECD

Reset

This register is loaded from nonvolatile location NVOPT during reset.

= Unimplemented or Reserved

Figure 4-3. Flash Options Register (FOPT)

Table 4-2. FOPT Field Descriptions

Field

Description

SECD

Security State Code — This bit field determines the security state of the MCU. When the MCU is secured, the

contents of Flash memory cannot be accessed by instructions from any unsecured source including the

background debug interface; refer to Section 4.6.4, “Security”.

0 Security engaged.

1 Security disengaged.

SC9RS08KA2 데이터시트(PDF) 32 Page - Freescale Semiconductor, Inc