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2.5 sec delay after power up

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I have a MSP430G2553 on a breadboard, loaded with a very simple Energia program. It is running at 1MHz with the internal oscillator. There is nothing attached to the reset pin. The program runs properly. But there is a 2.5 sec delay between the 3.3 volt supply coming up and the execution of the first line of the program (simply raising an output pin). That seems like a very long time. Is this normal? Is it due to hardware sequences on the chip or is it caused by Energia?

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Note that all global variables and objects, as well as a tiny bootstrap are run before the first line in your setup() or main() routine. So if you have a TCP/IP object in global space that tries to get an IP over DHCP, you might end up with several seconds of delay before the MCU enters the setup() or main().

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I use a standard 78L3.3 regulator for the supply. No large capacitor. It comes up to full voltage in less than 1msec.


It is my understanding that the reset pin has an internal pullup. Anyhow, when I add an external resistor and capacitor as recommended, the results are exactly the same.


For this test, I reduced my program to absolute minimum, just blinking one LED. No connections to the outside world.


The 2.5 sec delay is enough for many thousands of instructions. Does the Energia core really have that much setup work to do?

I would expect a few msecs at most.


Does anyone else have a measurement of their power up delay in similar circumstances?

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