MC9S12C Datasheet, PDF (476/680 Pages) Motorola, Inc – 16-Bit Microcontroller

Chapter 17 16 Kbyte Flash Module (S12FTS16KV1)
17.3.2.4 Flash Configuration Register (FCNFG)
The FCNFG register enables the Flash interrupts and gates the security backdoor key writes.
Module Base + 0x0003
7
6
5
4
3
2
1
0
R
0
0
0
0
0
CBEIE
CCIE
KEYACC
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 17-7. Flash Configuration Register (FCNFG)
CBEIE, CCIE, and KEYACC are readable and writable while remaining bits read 0 and are not writable.
KEYACC is only writable if the KEYEN bit in the FSEC register is set to the enabled state (see Section
17.3.2.2).
Table 17-7. FCNFG Field Descriptions
Field
7
CBEIE
6
CCIE
5
KEYACC
Description
Command Buffer Empty Interrupt Enable — The CBEIE bit enables the interrupts in case of an empty
command buffer in the Flash module.
0 Command Buffer Empty interrupts disabled
1 An interrupt will be requested whenever the CBEIF flag is set (see Section 17.3.2.6)
Command Complete Interrupt Enable — The CCIE bit enables the interrupts in case of all commands being
completed in the Flash module.
0 Command Complete interrupts disabled
1 An interrupt will be requested whenever the CCIF flag is set (see Section 17.3.2.6)
Enable Security Key Writing.
0 Flash writes are interpreted as the start of a command write sequence
1 Writes to the Flash array are interpreted as a backdoor key while reads of the Flash array return invalid data
17.3.2.5 Flash Protection Register (FPROT)
The FPROT register defines which Flash sectors are protected against program or erase.
Module Base + 0x0004
7
R
FPOPEN
W
6
NV6
5
FPHDIS
4
FPHS1
3
FPHS0
2
NV2
1
NV1
0
NV0
Reset
F
F
F
F
F
F
F
F
Figure 17-8. Flash Protection Register (FPROT)
The FPROT register is readable in normal and special modes. FPOPEN can only be written from a 1 to a 0.
FPHS[1:0] can be written anytime until FPHDIS is cleared. The FPROT register is loaded from Flash
address 0xFF0D during the reset sequence, indicated by F in Figure 17-8.
476
MC9S12C-Family / MC9S12GC-Family
Freescale Semiconductor
Rev 01.23