DS2790 Programmable 1-Cell Li-Ion Fuel Gauge and Protector

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IN-CIRCUIT DEBUG

Embedded debugging capability is available through the JTAG-compatible Test Access Port. Embedded debug

hardware and embedded ROM firmware provide in-circuit debugging capability to the user application, eliminating

the need for an expensive in-circuit emulator. Figure 21 shows a block diagram of the in-circuit debugger. The in-

circuit debug features include:

·

a hardware debug engine,

·

a set of registers able to set breakpoints on register, code, or data accesses

(ICDA, ICDB, ICDC, ICDD, ICDF, ICDT0, and ICDT1)

·

a set of debug service routines stored in the utility ROM.

Figure 21. In-Circuit Debugger

TMS

TCK

TDI

TDO

TAP

CONTROLLER

DEBUG

ENGINE

UTILITY ROM

DEBUG

SERVICE

ROUTINES

CPU

CONTROL

BREAKPOINT

ADDRESS

DATA

The embedded hardware debug engine is an independent hardware block in the microcontroller. The debug engine

can monitor internal activities and interact with selected internal registers while the CPU is executing user code.

Collectively, the hardware and software features allow two basic modes of in-circuit debugging:

·

Background mode allows the host to configure and set up the in-circuit debugger while the CPU continues

to execute the application software at full speed. Debug mode can be invoked from background mode.

·

Debug mode allows the debug engine to take control of the CPU, providing read/write access to internal

registers and memory, and single step trace operation.