Datasheet
LPC435X_3X_2X_1X All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4 — 19 August 2014 88 of 158
NXP Semiconductors
LPC435x/3x/2x/1x
32-bit ARM Cortex-M4/M0 microcontroller
There are three levels of the Code Read Protection:
• In level CRP1, access to the chip via the JTAG is disabled. Partial flash updates are
allowed (excluding flash sector 0) using a limited set of the ISP commands. This level
is useful when CRP is required and flash field updates are needed. CRP1 does
prevent the user code from erasing all sectors.
• In level CRP2, access to the chip via the JTAG is disabled. Only a full flash erase and
update using a reduced set of the ISP commands is allowed.
• In level CRP3, any access to the chip via the JTAG pins or the ISP is disabled. This
mode also disables the ISP override using P2_7 pin. If necessary, the application
code must provide a flash update mechanism using the IAP calls or using the
reinvoke ISP command to enable flash update via USART0. See Table 5
7.24 Serial Wire Debug/JTAG
Debug and trace functions are integrated into the ARM Cortex-M4. Serial wire debug and
trace functions are supported in addition to a standard JTAG debug and parallel trace
functions. The ARM Cortex-M4 is configured to support up to eight breakpoints and four
watch points.
Remark: Serial Wire Debug is supported for the ARM Cortex-M4 only,
The ARM Cortex-M0 coprocessor supports JTAG debug. A standard ARM
Cortex-compliant debugger can debug the ARM Cortex-M4 and the ARM Cortex-M0
cores separately or both cores simultaneously.
Remark: In order to debug the ARM Cortex-M0, release the M0 reset by software in the
RGU block.
CAUTION
If level three Code Read Protection (CRP3) is selected, no future factory testing can be
performed on the device.
Fig 10. Dual-core debug configuration
002aah448
ARM Cortex-M0
ARM Cortex-M4
TCK
DBGEN = HIGH
TMS
TRST
TDI
TDO
TDO
TDO
DBGEN
RESET = HIGH
RESET
TCK
TMS
TRST
TDI
TCK
TMS
TRST
TDI
JTAG ID = 0x0BA0 1477
JTAG ID = 0x4BA0 0477
LPC43xx