Debug Mode; Enable Debug Mode; User Manual - Philips LPC2101 User Manual

Philips Semiconductors
Volume 1

20.8 DEBUG mode

The Debug mode connects the JTAG pins to the embedded ICE for program debugging
using an emulator or other development tool

20.8.1 Enable Debug mode

The Debug mode is enabled through the use of the DBGSEL and RTCK pins.
To enable the debug mode, DBGSEL must be HIGH during and after the CPU is reset.
For normal (non-debug) operation, DBGSEL must be kept LOW at all times (see
Figure
For debugging with JTAG pins, RTCK must be HIGH as the RST pin is released (see
Figure
pull-up. The RTCK output driver is disabled until the internal wake-up time has expired,

User manual

serial
parallel
EMBEDDED ICE
interface
INTERFACE
PROTOCOL
CONVERTER
host running debugger
Fig 64. EmbeddedICE debug environment block diagram
65)
RST
1
DBGSEL
2
RTCK
(1) DBDSEL is tied or pulled LOW at all times. An internal pull-down will cause DBGSEL to be
LOW if it is not pulled HIGH externally.
(2) RTCK is not connected in the application and is pulled up internally.
Fig 65. Waveforms for normal operations (not in debug mode)
66). RTCK may be driven HIGH externally or allowed to float HIGH via its on-chip
Rev. 01 — 12 January 2006
Chapter 20: EmbeddedICE
JTAG PORT
5
EMBEDDED ICE
ARM7TDMI-S
TARGET BOARD
.
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
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