reset every time at the end of program

Projects General Guidance
1

Hi there,

I met a very weird problem. Every time arduino runs to the end of program, it doesn't run from the beginning of loop() but reset it self and execute program in setup().

My program just did some serial port write to control the 3g shield.

Is it probably caused by serial port ?

2

Where is your program?
Are you running out of ram?

3

Doing something that causes a current surge & thus a reset?
Or overfilling some buffer, running out of SRAM?

4

LarryD:
Where is your program?
Are you running out of ram?

Running out of code box pixels.