[SOLVED] LPC1768 (cortex m3)board not working

[nevasith]

[solved ]LPC1768 (cortex m3)board not working

Hi, I have built a small board with LP1768 microcontroller and powered it up - obviously something is wrong, but I can't seem to trace the problem. My question is about generic suggestions on how to solve such problems. Perhaps someone worked with those CPUs and knows potential problem.

The clocks are dead (I mean no oscillation seen on both RTC or XTAL when i connect oscilloscope there), the board also refuses to work with its internal oscillator.

When I connect the programmer (keil for mcb1700) the keil uvision programs the board and suggests everything is in order and complains if I disconnect the board.

Could someone recommend me what should I check to find why the board is not working(what steps to find the source of problem)


Thanks for any help
Regards

 

[nevasith]

For future generations:

Port 2[10]/ EINT0 is also used to drive the device into ISP mode if pulled low during boot-up. The problem wac comming from radio module that was holding it low on its own power up, and since they were powered up at the same time the LPC1768 was going into ISP mode and stayed there forever.

SOLUTION:
Pull up EINT0 pin during boot up.