MC9S12E256 Datasheet, PDF (94/602 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 2 256 Kbyte Flash Module (FTS256K2V1)
Table 2-11. FPROT Field Descriptions (continued)
Field
Description
2
FPLDIS
Flash Protection Lower address range Disable — The FPLDIS bit determines whether there is a
protected/unprotected area in the lower address space of the Flash block.
0 Protection/Unprotection enabled
1 Protection/Unprotection disabled
1:0
Flash Protection Lower Address Size — The FPLS[1:0] bits determine the size of the protected/unprotected
FPLS[1:0] area as shown in Table 2-14. The FPLS[1:0] bits can only be written to while the FPLDIS bit is set.
Table 2-12. Flash Protection Function
FPOPEN
FPHDIS FPLDIS
Function¹
1
1
1
No Protection
1
1
0
Protected Low Range
1
0
1
Protected High Range
1
0
0
Protected High and Low Ranges
0
1
1
Full Block Protected
0
1
0
Unprotected Low Range
0
0
1
Unprotected High Range
0
0
0
Unprotected High and Low Ranges
1 _{For range sizes, refer to Table 2-13 and Table 2-14.}
FPHS[1:0]
00
01
10
11
Table 2-13. Flash Protection Higher Address Range
Unpaged
Address Range
0xF800–0xFFFF
0xF000–0xFFFF
0xE000–0xFFFF
0xC000–0xFFFF
Paged
Address Range
0x0037/0x003F: 0xC800–0xCFFF
0x0037/0x003F: 0xC000–0xCFFF
0x0037/0x003F: 0xB000–0xCFFF
0x0037/0x003F: 0x8000–0xCFFF
Protected Size
2 Kbytes
4 Kbytes
8 Kbytes
16 Kbytes
FPLS[1:0]
00
01
10
11
Table 2-14. Flash Protection Lower Address Range
Unpaged
Address Range
0x4000–0x43FF
0x4000–0x47FF
0x4000–0x4FFF
0x4000–0x5FFF
Paged
Address Range
0x0036/0x003E: 0x8000–0x83FF
0x0036/0x003E: 0x8000–0x87FF
0x0036/0x003E: 0x8000–0x8FFF
0x0036/0x003E: 0x8000–0x9FFF
Protected Size
1 Kbyte
2 Kbytes
4 Kbytes
8 Kbytes
All possible Flash protection scenarios are illustrated in Figure 2-9. Although the protection scheme is
loaded from the Flash array after reset, it can be changed by the user. This protection scheme can be used
by applications requiring re-programming in single-chip mode while providing as much protection as
possible if re-programming is not required.
MC9S12E256 Data Sheet, Rev. 1.08
94
Freescale Semiconductor