EM357-RTR datasheet(216/240 Pages) ETC2

216 / 240 page

EM351 / EM357

15 Flash Patch and Breakpoint (FPB)

The EM35x integrates the standard ARM® Flash Patch and Breakpoint (FPB). The FPB implements hardware

breakpoints. The FPB also provides support for remapping of specific instruction or literal locations from flash

memory to an address in RAM memory. The FPB contains:

Two literal comparators for matching against literal loads from flash space, and remapping to a

corresponding RAM space.

Six instruction comparators for matching against instruction fetches from flash space, and remapping to a

corresponding RAM space. Alternatively, the comparators can be individually configured to return a

breakpoint instruction to the processor core on a match, implementing hardware breakpoint capability.

The FPB contains a global enable, but also individual enables for the eight comparators. If the comparison for

an entry matches, the address is remapped to the address defined in the remap register plus and offset

corresponding to the comparator that matched. Alternately, the address is remapped to a breakpoint

instruction. The comparison happens on the fly, but the result of the comparison occurs too late to stop the

original instruction fetch or literal load taking place from the flash space. The processor ignores this

transaction, however, and only the remapped transaction is used.

Memory Protection Unit (MPU) lookups are performed for the original address, not the remapped address.

Unaligned literal accesses are not remapped. The original access to the bus takes place in this case.

The FPB is designed for use with advanced debug tools, available from multiple vendors. Altering FPB

configuration may conflict with the operation of advanced debug tools.

For further information on the FPB, contact Ember support for the ARM® CortexTM-M3 Technical Reference

Manual, the ARM® CoreSightTM Components Technical Reference Manual, the ARM® v7-M Architecture

Reference Manual, and the ARM® v7-M Architecture Application Level Reference Manual.

15-1

120-035X-000D

Preliminary

EM357-RTR 数据表(PDF) 216 Page - List of Unclassifed Manufacturers