15: Target error from Register access

Showing results for 
Show  only  | Search instead for 
Did you mean: 

15: Target error from Register access

Contributor III


   I am using LPC54608 development board (OM13092) for evaluation. I am trying to switch the main clock to external clock but i am facing the error "15: Target error from Register access" when connecting to the debug.

   I have attached code and the error message . Please help.

Thanks and best regards,


Labels (1)
Tags (1)
0 Kudos
1 Reply

NXP Employee
NXP Employee


Please check the attached initialization code. 

If your external osc is not workable, you can't even debug code. for example, during clock initialization, when you execute/debug code of switch MAIN_CLK to  to system PLL, debug fails and loses connection.


To check clock setting, you can set CLKOUTSELA register to orient clk_in or main_clk or pll_clk to CLKOUT pin, measure this pin with scope. see if the output is correct.


if your external OSC configuration is wrong, normally the code will be stuck there during running; if you are doing debug, you will see debug lose connection during clock configuration code. The popped up error message such as " Target error from register access",etc.


It will not switch to internal FRO automatically by MCU when external crystal osc is failed.

Have a great day,

- If this post answers your question, please click the "Mark Correct" button. Thank you!

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.

0 Kudos