Thanks! > On May 20, 2015, at 1:33 PM, [email protected] wrote: > > > <https://lh3.googleusercontent.com/-NW_qX1Cz0Vk/VVzTguPp-RI/AAAAAAAADKs/NIVwCCQ1PLM/s1600/Screen%2BShot%2B2015-05-21%2Bat%2B02.25.52.jpeg>Hi > there folks, > > The CircuitCo LCD3 cape version A2 basically pulls up the backlight supply > enable line via R126. By removing R126, and adding a 0R resistor (or a blob > of solder) on the pads for R123, you enable use of the EHRPWM1A line to > control the backlight. > > The caveat is that when you power up the BBB, you should issue a > > echo 50 > /sys/class/backlight/backlight/brightness > > to have anything come up on the BBB LCD3. > > Cheers! > > > > - Antonio > > On Friday, 30 May 2014 02:43:06 UTC+8, john3909 wrote: > > From: Colin Bester <[email protected] <javascript:>> > Reply-To: <[email protected] <javascript:>> > Date: Thursday, May 29, 2014 at 6:45 AM > To: <[email protected] <javascript:>> > Subject: Re: [beagleboard] BBB LCD3 Cape and inactivity > > I just managed to get around to looking a little deeper into this and > connected an oscilloscope to EHRPWM1A (which I figure is pin P9_14) and > confirm that when writing a zero to brightness (using echo 0 > > /sys/class/backlight/backlight.11/brightness) that the pin is low. Likewise > write a ’50’ sets a 50% duty cycle and LCD brightens. I haven’t set up > environment to compile and test using ‘c’ files yet. > > With low on pin P9_14 the LCD is still visible. > In that case this is a hardware issue. P9_14 is connected to the enable pin > of the LED backplane driver so the leds should turn off. > > Regards, > John > > With debian version I now have running, I have not seen the LCD goto sleep > yet - still have to look into this. > > ~C > > > On May 26, 2014, at 8:03 PM, John Syn <[email protected] <javascript:>> wrote: > >> >> From: Colin Bester <[email protected] <javascript:>> >> Reply-To: <[email protected] <javascript:>> >> Date: Monday, May 26, 2014 at 4:54 PM >> To: <[email protected] <javascript:>> >> Subject: Re: [beagleboard] BBB LCD3 Cape and inactivity >> >>> Was wondering if you have come up with any further solution? I can write >>> '0' to backlight brightness but while this dims the display significantly >>> it doesn't switch if off. >> >> Have you checked that EHRPWM1A is low when you dim the display? Here are two >> files that will control the backlight. >> >> /driver/video/backlight/pwm_bl.c >> /driver/pwm/pwm-tiehrpwm.c >> >> Regards >> John > > > > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to a topic in the Google > Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/d_6HC6ps2RU/unsubscribe > <https://groups.google.com/d/topic/beagleboard/d_6HC6ps2RU/unsubscribe>. > To unsubscribe from this group and all its topics, send an email to > [email protected] > <mailto:[email protected]>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>.
-- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
