Several observations. When pressing power button or executing halt instruction, processor does shutdown but the voltage rails SYS_5V and VLD02 don't (I didn't check VLDO01). VLDO2 does drop to less than 2V but appears to still be enough to trigger U4 TL5209's enable pin thus switching SYS_5V to VDD_3V3B. This to me doesn't look right, this level (VLD02) should either be asserted or negated and not in between levels.
Powering up with just battery and no 5V (not pressing any buttons) shows SYS-5V active high (5V) and VLD02 at expected 0V. Looks to me like there is a power switching problem although fixing this still won't fix the issue I am having as I want to totally switch off LCD4 which is using SYS_5V for backlight. I am not sure from the tech notes if it's possible or not to switch off SYS_5V voltage (Pins 7.8 SYS1/SYS2 on TPS65217C). If one can't then my question to LCD module supplier/manufacturer is how did they intend us to shut device down with a battery connected. ~C On Monday, June 23, 2014 6:52:03 PM UTC-5, john3909 wrote: > > > Power Button is also on P9 Pin 9. BTW, sudo halt powers off all power > rails and is functionally equivalent to holding the power button for 10 > seconds. If your LCD backlight is still on, then it is powered from the 5V > rail because all other power rails are off. > > Regards, > John > > > -- 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.
