On Tue, 2014-03-25 at 10:33 +0100, Alexander Stein wrote: > > According to the datasheet, writing to the level register has no effect > when GPIO is programmed as input. Hence we set the level after configuring > the GPIO as output. But we cannot prevent a short low pulse if direction is > set to high and an external pull-up is connected.
Does "will have no effect" actually translate into "should not be done" or even "must not be done"? Doesn't sound like it. I understood that setting the data register for input pins does nothing in that very moment, yet when switching to output the value immediately gets used. So this is the most appropriate thing to do. virtually yours Gerhard Sittig -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr. 5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: [email protected] -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
