Memory Protection Unit (MPU)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
17-6
Freescale Semiconductor
Preliminary
17.3.2.2
MPU Error Address Register, MPU Port 0 to 2 (MPU_EARn)
When the MPU detects an access error on MPU port
n
, the 32-bit reference address is captured in this
read-only register and the corresponding bit in the MPU_CESR[MPERR] field set. Additional information
about the faulting access is captured in the corresponding MPU_EDR
n
register at the same time.
Table 17-2. MPU_CESR Field Descriptions
Field
Description
MPERR
MPU Port n Error, where the MPU port number matches the bit number. Each bit in this read-only field represents a
flag maintained by the MPU for signaling the presence of a captured error contained in the MPU_EARn and
MPU_EDRn registers. The individual bit is set when the hardware detects an error and records the faulting address
and attributes. It is cleared when the corresponding bit is written to a logical one. If another error is captured at the
exact same cycle as a write of a logical one, this flag remains set. A find-first-one instruction (or equivalent) can be
used to detect the presence of a captured error.
0 The corresponding MPU_EARn/MPU_EDRn registers do not contain an unread captured error
1 The corresponding MPU_EARn/MPU_EDRn registers do contain an unread captured error
Note: Bit 0 indicates a flash port 0 access protection error, bit 1 a combined Flash Port 1/EBI/peripheral bridge
protection error, and bit 3 an SRAM protection error.
HRL
Hardware Revision Level. This 4-bit read-only field specifies the MPU’s hardware and definition revision level. It can
be read by software to determine the functional definition of the module. This field reads as 0 on MPC5510.
NSP
Number of MPU/Slave Ports. This 4-bit read-only field specifies the number of MPU/slave ports [1–8] connected to
the MPU.
This field reads as 0b0011 on MPC5510.
NRGD
Number of Region Descriptors. This 4-bit read-only field specifies the number of region descriptors implemented in
the MPU. The defined encodings include:
0000 8 region descriptors
0010 16 region descriptors
This field reads as 0b0010 on MPC5510
VLD
Valid. This bit provides a global enable/disable for the MPU.
0 The MPU is disabled
1 The MPU is enabled
While the MPU is disabled, all accesses from all bus masters are allowed.
Offset: MP 0x0010 (MPU_EAR0)
MP 0x0018 (MPU_EAR1)
MP 0x0020 (MPU_EAR2)
Access: User read only
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
EADDR
W
Reset –
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Figure 17-3. MPU Error Address Register, Slave Port n (MPU_EARn)
Table 17-3. MPU_EARn Field Descriptions
Field
Description
EADDR
Error Address. This read-only field is the reference address from slave port n that generated the access error.