No worries...you're actually correct if we were talking about SYS_5V (on P9 pins 7 and 8) instead of VDD_5V (P9 pins 5 and 6).
The SRM section you reference is a bit confusing, as it talks about drawing power from that rail and not powering the board with it. I almost always fall back to the schematic as the "primary source" for how things work, and there's other sections in the SRM (6.1.2, page 42 and 8.6.2, page 110/111) that talk about powering the board with 5V via the expansion connector. On 12/23/2013 6:38 PM, Daniel Metcalf wrote: > I stand corrected ... like I said I am a newbie to the BBB. > > Respectfully, > Dan Metcalf > On Dec 23, 2013 7:27 PM, "Charles Steinkuehler" <[email protected]> > wrote: > >> Actually, VDD_5V is raw 5V power, connected directly to the DC power >> jack. It is absolutely possible to power the BeagleBoard this way, and >> I have several capes that do so and work just fine (the BeBoPr and K9) >> powering the 'Bone via VDD_5V. >> >> The LED behavior likely indicates something is going wrong with booting >> the operating system. The easiest way to debug these issues is with a >> serial port cable, so you can see what's happening. As a guess, you may >> be tying some other pins (specifically the LCD_DATA lines) to circuitry >> and messing up the AM335x boot process. By changing the values on these >> signals at reset, you can determine if the CPU should boot from eMMC >> flash, SD card, ethernet, USB, serial, etc., so messing this up can >> easily result in a system that won't boot. >> >> Double-check the LCD_DATA lines, and get a serial debug cable so you can >> see what's going on. >> >> On 12/23/2013 3:05 PM, Daniel Metcalf wrote: >>> I am not sure you can power it that way. I am a newbie to beaglebone >> black >>> but checkout page 110 of 124. >>> Pin 5 of J9 is VDD_5V which is described as the following: >>> >>> *VDD_5V *is the main power supply from the DC input jack. This voltage is >>> not present when the board is powered via USB. The amount of current >>> supplied by this rail is dependent upon the amount of current available. >>> Based on the board design, this rail is limited to 1A per pin from the >> main >>> board. >>> >>> I believe it is an output from a regulator. >>> >>> You are going to want to connect to TP5 - BAT, TP8 - GND, TP6 - SENSE >>> >>> >>> >>> >>> On Mon, Dec 23, 2013 at 3:30 PM, José Luis Redrejo <[email protected] >>> wrote: >>> >>>> I've made a power supply to power my BBB, but whenever I connect it >>>> (to pins 5 & 1 of P9 connector for VDD & GND), the power led blinks >>>> for some seconds and then it is off. >>>> >>>> The output comes from a 7805CKCT, which can provide up to 1.5A. >>>> >>>> It's a typical power supply from a rectifier + capacitors + regulator. >>>> >>>> What does this "blinking" mean? any ideas of what is going wrong? >>>> >>>> Regards >>>> José L. >>>> >>>> P.S. The board works perfectly plugging it to a computer via USB >>>> >>>> -- >>>> 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/groups/opt_out. >>>> >>> >>> >>> >> >> >> -- >> Charles Steinkuehler >> [email protected] >> >> -- >> 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/groups/opt_out. >> > -- Charles Steinkuehler [email protected] -- 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/groups/opt_out.
