ARM Technical Support Knowledge Articles


Applies to: ULINK USB-JTAG Debugger


Information in this knowledgebase article applies to:


When I try to download my application into the flash of a new LPC17xx device via ULINK2/ULINK-ME/ULINKpro USB-JTAG Adapter, programming works very slow and then I receive the message:

"Flash Timeout. Reset the Target and try again"
and then
"Flash Download failed".

This only happens when I program a LPC17xx device that is new or was completely erased before. When an application was previously loaded, everything works as expected.


NXP LPC17xx devices have an on-chip bootloader that initializes the PLL0 and the CPU clock divider (CCLKCFG) after a reset when there is no application loaded into the flash or when pin INT0 is pulled low. Our flash algorithm disabled the PLL0 but did not initialize the CCLKCFG register.


This issue is solved with the attached Flash algorithms. Please download the attached ZIP file and extract it to your C:\Keil\ARM\Flash folder. If you did not install the MDK to C:\Keil, please adapt the path accordingly.

This patch is already included in MDK releases later than version 4.54.


Request the files attached to this knowledgebase article.

Article last edited on: 2012-08-20 07:59:36

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