Code Security Vs Debugging - Philips LPC213 Series User Manual

Philips Semiconductors
Volume 1
But when Brown-Out Detection is enabled to bring the LPC2131/2/4/6/8 out of
Power-Down mode (which is itself not a guaranteed operation -- see
Control register (PCON - 0xE01F
transient before the Wakeup Timer has completed its delay. In this case, the net result of
the transient BOD is that the part wakes up and continues operation after the instructions
that set Power-Down Mode, without any interrupt occurring and with the BOD bit in the
RISR being 0. Since all other wakeup conditions have latching flags (see
"External Interrupt Flag register (EXTINT - 0xE01F C140)"
Location Register (ILR - 0xE002 4000)" on page
apparent cause, can be assumed to be a Brown-Out that has gone away.

3.13 Code security vs debugging

Applications in development typically need the debugging and tracing facilities in the
LPC2131/2/4/6/8. Later in the life cycle of an application, it may be more important to
protect the application code from observation by hostile or competitive eyes. The following
feature of the LPC2131/2/4/6/8 allows an application to control whether it can be
debugged or protected from observation.
Details on the way Code Read Protection works can be found in the "Flash Memory
System and Programming" chapter on page 216.
User manual
COCO)"), the supply voltage may recover from a
Rev. 01 — 24 June 2005
UM10120
Chapter 3: System Control Block
Section 3.8.2 "Power
and Section 18.4.3 "Interrupt
202), a wakeup of this type, without any
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
Section 3.5.2
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