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LPC2xxx GPIO Outputs Born LOW

2004-10-26 by markcrow

I was surprised to discover that GPIO pins, just after they're 
configured as outputs, default LOW (the opposite state of its startup 
high-impedance input mode).  For my design, LOW is an ACTIVE state.  
I can immediately set the output HIGH but I'm stuck with a 
LOW 'glitch' to deal with.  Every other micro GPIO I've worked with 
would maintain the HIGH when switching from input to output mode.

Just wondering if anyone knows something I don't here...I certainly 
can't find any Philips documentation on the issue.  And I know I can 
design for a HIGH state and put pulldowns on the lines but, again, I 
hate to redo everything just to find that the initial GPIO output 
state is undefined or arbitrary...or, again, that there's something I 
dont' know about.

Thanks folks,

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