Datasheet

Table 3-3. TEX, S, C, and B Bit Field Encoding (continued)
Other AttributesShareabilityMemory TypeBCSTEX
Cached memory (BB =
outer policy, AA = inner
policy).
See Table 3-4 for the
encoding of the AA and
BB bits.
Not shareableNormalAA01BB
ShareableNormalAA11BB
a. The MPU ignores the value of this bit.
Table 3-4 on page 105 shows the cache policy for memory attribute encodings with a TEX value in
the range of 0x4-0x7.
Table 3-4. Cache Policy for Memory Attribute Encoding
Corresponding Cache PolicyEncoding, AA or BB
Non-cacheable00
Write back, write and read allocate01
Write through, no write allocate10
Write back, no write allocate11
Table 3-5 on page 105 shows the AP encodings in the MPUATTR register that define the access
permissions for privileged and unprivileged software.
Table 3-5. AP Bit Field Encoding
DescriptionUnprivileged
Permissions
Privileged
Permissions
AP Bit Field
All accesses generate a permission fault.No accessNo access000
Access from privileged software only.No accessR/W001
Writes by unprivileged software generate a
permission fault.
ROR/W010
Full access.R/WR/W011
Reserved.UnpredictableUnpredictable100
Reads by privileged software only.No accessRO101
Read-only, by privileged or unprivileged software.RORO110
Read-only, by privileged or unprivileged software.RORO111
MPU Configuration for a Stellaris Microcontroller
Stellaris microcontrollers have only a single processor and no caches. As a result, the MPU should
be programmed as shown in Table 3-6 on page 105.
Table 3-6. Memory Region Attributes for Stellaris Microcontrollers
Memory Type and AttributesBCSTEXMemory Region
Normal memory, non-shareable, write-through010000bFlash memory
Normal memory, shareable, write-through011000bInternal SRAM
Normal memory, shareable, write-back,
write-allocate
111000bExternal SRAM
Device memory, shareable101000bPeripherals
105June 18, 2012
Texas Instruments-Production Data
Stellaris
®
LM3S8962 Microcontroller
NRND: Not recommended for new designs.