Hello all, I'm being just a little bit careful here:
I'm about to try this, but I will connect up the serial terminal first, so I can see output and interact with the board. (Graceful shutdown!) I will test the serial connection first with just a micro USB charging cable rather than USB to a computer. (Simplify!) It's my understanding that LiPo charging is disabled or not present in the firmware. (I'll give you the "uname -a" and other info the next time I fire it up. Just let me know what and how to check.) Also, it's not clear (without reading the data sheet :) ) about the resistor values for the thermistor and the parallel (linearizing?) resistor. If you have a 10K thermistor, do you put it in parallel with a 10K resistor, or likewise 100K thermistor in parallel with a 100K resistor? Do you put the thermistor anywhere in contact with the (e.g., 18650) LiPo? >From the prior thread, it seems to be sufficient (if even necessary) just to connect a 10K resistor from TS (P2-16) to ground (P2-15). 10uF cap from battery (P2-14) to ground (P2-15). (Tangent/future: What about larger cap, perhaps using a 5.5V supercap, detect supercap discharging (lipo voltage to ~min input voltage on vbat) and give an interrupt to shut the board down?) Thanks in advance for your help, and to the original thread authors! Other posts that I found: Safely power down the PocketBeagle supplied by a battery (no replies?): https://groups.google.com/d/msg/beagleboard/dDSD89DGzpU/j2WzZyA2CgAJ Supplying two ICs from the PocketBeagle powered by a Lipo battery https://groups.google.com/d/msg/beagleboard/B7Zyf97hvzY/z8cOt0MHBwAJ I want to do some excessive self-telemetry, both internal and external. I plan to scale the raw battery voltage by 1/11 with an op amp before feeding to one of the 1.8V ADC inputs. I'll defer to suggestions about measuring current. (This is a tangent: I also plan to be paranoid if I connect to a car and want to monitor the car's "12V" with something like a VCO on the car side pulsing to an optoisolator, but I'm sure there are better ideas out there! :) (I could use several PIC -> nrf24l01 for some "really good" isolation!) Thanks, Fred Kerr On Friday, November 10, 2017 at 10:32:46 AM UTC-8, Adam Saenz wrote: > > Keep in mind that the 7V is Absolute Max voltage so you should operate > below this level or risk damaging the chip. > > > > On Thursday, November 9, 2017 at 10:15:05 PM UTC-8, Shannon Mackey wrote: >> >> >> I expect I'm overlooking something, But it isn't obvious to me how to >> power the PocketBeagle with batteries. It doesn't have a similar >> arrangement to BBB. Can someone point me in the right direction, please? >> Thanks! >> >> -- 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 beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/e24b6a8a-365b-440a-b536-54b174a97c14%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
