SAM7X128_14 Datasheet, PDF (195/662 Pages) ATMEL Corporation – ARM-based Flash MCU

26. Debug Unit (DBGU)
26.1 Overview
The Debug Unit provides a single entry point from the processor for access to all the debug capabilities of Atmel’s ARM-
based systems.
The Debug Unit features a two-pin UART that can be used for several debug and trace purposes and offers an ideal
medium for in-situ programming solutions and debug monitor communications. The Debug Unit two-pin UART can be
used standalone for general purpose serial communication. Moreover, the association with two peripheral data controller
channels permits packet handling for these tasks with processor time reduced to a minimum.
The Debug Unit also makes the Debug Communication Channel (DCC) signals provided by the In-circuit Emulator of the
ARM processor visible to the software. These signals indicate the status of the DCC read and write registers and
generate an interrupt to the ARM processor, making possible the handling of the DCC under interrupt control.
Chip Identifier registers permit recognition of the device and its revision. These registers inform as to the sizes and types
of the on-chip memories, as well as the set of embedded peripherals.
Finally, the Debug Unit features a Force NTRST capability that enables the software to decide whether to prevent access
to the system via the In-circuit Emulator. This permits protection of the code, stored in ROM.
SAM7X Series [DATASHEET]
6120K–ATARM–11-Feb-14
195