Chapter 28 256 Kbyte Flash Module (S12XFTX256K2V1)
MC9S12XDP512 Data Sheet, Rev. 2.17
Freescale Semiconductor
1157
CBEIE, CCIE and KEYACC bits are readable and writable while all remaining bits read 0 and are not
writable in normal mode. KEYACC is only writable if KEYEN (see
Section 28.3.2.2, “Flash Security
Register (FSEC)”
is set to the enabled state. BKSEL is readable and writable in special mode to simplify
mass erase and erase verify operations. When writing to the FCNFG register in special mode, all
unimplemented/ reserved bits must be written to 0.
28.3.2.5
Flash Protection Register (FPROT)
The FPROT register defines which Flash sectors are protected against program or erase operations.
7
6
5
4
3
2
1
0
R
CBEIE
CCIE
KEYACC
0
0
0
0
0
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 28-8. Flash Configuration Register (FCNFG — Normal Mode)
7
6
5
4
3
2
1
0
R
CBEIE
CCIE
KEYACC
0
0
0
0
BKSEL
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 28-9. Flash Configuration Register (FCNFG — Special Mode)
Table 28-8. FCNFG Field Descriptions
Field
Description
7
CBEIE
Command Buffer Empty Interrupt Enable
— The CBEIE bit enables an interrupt in case of an empty command
buffer in the Flash module.
0 Command buffer empty interrupt disabled.
1 An interrupt will be requested whenever the CBEIF flag (see
Section 28.3.2.6, “Flash Status Register
(FSTAT)”)
is set.
6
CCIE
Command Complete Interrupt Enable
— The CCIE bit enables an interrupt in case all commands have been
completed in the Flash module.
0 Command complete interrupt disabled.
1 An interrupt will be requested whenever the CCIF flag (see
Section 28.3.2.6, “Flash Status Register (FSTAT)”
)
is set.
5
KEYACC
Enable Security Key Writing
0 Flash writes are interpreted as the start of a command write sequence.
1 Writes to Flash array are interpreted as keys to open the backdoor. Reads of the Flash array return invalid
data.
0
BKSEL
Block Select
— The BKSEL bit indicates which register bank is active.
0 Select register bank associated with Flash block 0.
1 Select register bank associated with Flash block 1.