UM10237_2 © NXP B.V. 2008. All rights reserved.
User manual Rev. 02 — 19 December 2008 680 o f 792
NXP Semiconductors UM10237
Chapter 30: LPC24XX Flash memory programming firmware
6. Boot process flowchart

(1) For details on handling the crystal frequency, see Section 30–10.8 “Reinvoke ISP” on page 695

(2) For details on available ISP commands based on the CRP settings see Section 30–8 “Code Read Protection (CRP)

Fig 139. Boot process flowchart

WATCHDOG
FLAG SET?
CRP1/2/3 ENABLED?
yes
no
INITIALIZE
RESET
ENABLE DEBUG
yes
RUN ISP COMMAND
HANDLER
2
RECEIVE CRYSTAL
FREQUENCY
1
no AUTO-BAUD
SUCCESSFUL?
yes
RUN AUTO-BAUD
USER CODE
VALID?
yes
no
CRP3 ENABLED?
Enter ISP
MODE?
(P2.10=LOW)
USER CODE VALID?
yes
yes
no
yes
no no
A
A
EXECUTE INTERNAL
USER CODE