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I am a newbie to ARM7.I have a LPC2148 controller and a JTAG debugger.I have tried running a small led blinking code.In debug mode the led blinks but as soon as I'm out of the debug mode ,the led stops blinking and there is no response from the microcontroller.After I hit reset there is still no response.I read somewhere that it is essential to inset the program signature in the startup file.Can anyone help me in doing this?I would need the example of the startup file with the program signature and the method to calculate it with an example.Thank you
step 1: have you tried Keil's blinky for your chip?
Yes I have tried running this program as well as the Hello world program.I am using Keil uvision 4 version.
www.nxp.com/.../UM10139.pdf
21.4.2 Criterion for valid user code
Criterion for valid user code: The reserved ARM interrupt vector location (0x0000 0014) should contain the 2's complement of the check-sum of the remaining interrupt vectors. This causes the checksum of all of the vectors together to be 0. The boot loader code disables the overlaying of the interrupt vectors from the boot block, then checksums the interrupt vectors in sector 0 of the flash. If the signatures match then the execution control is transferred to the user code by loading the program counter with 0x0000 0000. Hence the user flash reset vector should contain a jump instruction to the entry point of the user application code.