The Embedded Trace Macrocell (ETM) delivers unrivaled instruction trace capture in an area smaller
than traditional trace units, enabling full instruction trace. For more details on the ARM ETM, see
the
ARM® Embedded Trace Macrocell Architecture Specification
.
The Flash Patch and Breakpoint Unit (FPB) provides up to eight hardware breakpoint comparators
that debuggers can use. The comparators in the FPB also provide remap functions for up to eight
words of program code in the code memory region. This FPB enables applications stored in a
read-only area of Flash memory to be patched in another area of on-chip SRAM or Flash memory.
If a patch is required, the application programs the FPB to remap a number of addresses. When
those addresses are accessed, the accesses are redirected to a remap table specified in the FPB
configuration.
For more information on the Cortex-M4F debug capabilities, see the
ARM® Debug Interface V5
Architecture Specification
.
2.2.3
Trace Port Interface Unit (TPIU)
The TPIU acts as a bridge between the Cortex-M4F trace data from the ITM, and an off-chip Trace
Port Analyzer, as shown in Figure 2-2 on page 83.
Figure 2-2. TPIU Block Diagram
ARM® Trace
Bus (ATB)
Interface
Asynchronous FIFO
Advance
Peripheral
Bus (APB)
Interface
Trace Out
(serializer)
Debug
ATB
Slave
Port
APB
Slave
Port
Serial Wire
Trace Port
(SWO)
2.2.4
Cortex-M4F System Component Details
The Cortex-M4F includes the following system components:
■ SysTick
A 24-bit count-down timer that can be used as a Real-Time Operating System (RTOS) tick timer
or as a simple counter (see “System Timer (SysTick)” on page 135).
■ Nested Vectored Interrupt Controller (NVIC)
83
June 18, 2014
Texas Instruments-Production Data
Tiva
™
TM4C1294NCPDT Microcontroller