I/O State

nambip2 · ‎2005-04-24

Posted on April 25, 2005 at 05:03

I/O State

nambip2 · ‎2005-04-20

Posted on April 20, 2005 at 18:12

In ST7FLITE09 , after power up how long does it take for the configuration of the I/O when i use the internal RC oscillator ? In my application i like to configure the I/O as O/P .

1. From power up until configuration of the I/O as O/P what will be the state of the I/O Pin.will this be high impedance / low / high ?

2 .From power up to valid output (I/O config.) what is the time taken ?

Thanks

Prasanna

alok2 · ‎2005-04-24

Posted on April 25, 2005 at 05:03

This is explained in datasheet. See Reset Sequence Manager chapter.

To answer a bit..

1. Startup time of micro : 256 cyc + PLL startup time (60 cyc) + S/w initialisation time if taken by compiler library (e.g startup.o)

2. I/o are in floating i/p = high impedance

3. once the mcu has started, you can put 1st instruction for IO initialisations.

hope it helps.