I'm kind of at a standstill. I found a circuit design to use a transistor to take a 3.3v input, and switch on the 5v for the GPS but then while doing more reading someone said that was a really bad idea because they weren't opto-isolated. I didn't really know what that was, but after reading it makes a little more sense. If the transistor fails or is otherwise damaged, it could end up feeding 5v into the 3.3v section of the Beagleboard and fry it.
I was looking for an opto-isolated transistor relay, found one but haven't gotten one ordered yet to try it out. That's pretty much the status, I was going to try and talk to an electrical engineer friend of mine to see what he thought of the situation. What do you think? Thanks, Dan On Wed, Feb 13, 2019 at 8:17 PM Mala Dies <[email protected]> wrote: > Hey Man, > > Seth here. Did you ever figure out the issue w/ setting up a GPIO pin to > control the 5v for your GPS? > > Seth > > On Sunday, February 10, 2019 at 12:38:52 AM UTC-6, Dan Hammans wrote: >> >> No apologies needed, I'm just trying to figure this out. What I meant >> was using a GPIO pin to trigger the relay/transistor which would then >> switch on +5v. >> >> I'll take a look at the links above, appreciate your help! >> >> On Saturday, February 9, 2019 at 11:58:08 PM UTC-6, Mala Dies wrote: >>> >>> Sir, >>> >>> I just found a source for ideas: >>> https://next-hack.com/index.php/2017/09/15/how-to-interface-a-5v-output-to-a-3-3v-input/. >>> Adding a button and software could prove valuable. If anything, it may help >>> a bit. >>> >>> Seth >>> >>> P.S. GPIO works for buttons, LEDs, and other circuitry. I am sure you >>> know how to do things. I was trying to latch on to learn more. Sorry. >>> >>> On Saturday, February 9, 2019 at 11:19:47 PM UTC-6, Dan Hammans wrote: >>>> >>>> Hi Seth, I really appreciate the reply. >>>> >>>> I was afraid of that. My GPS module requires +5v. Is there another +5v >>>> source on the board that is switched off when the board powers down? What >>>> about the black power connector above the GPS UART port? >>>> >>>> Otherwise it looks like I will be building a resistor circuit and >>>> triggering it from a GPIO pin. >>>> >>>> On Saturday, February 9, 2019 at 11:07:14 PM UTC-6, Mala Dies wrote: >>>>> >>>>> Sir, >>>>> >>>>> Seth here. I just got done dealing w/ someone on this subject. The 5v >>>>> pin from the GPS connection cannot be "un"powered. It stays powered on >>>>> while the board has power. >>>>> >>>>> Seth >>>>> >>>>> P.S. Try UART instead at 3.3v. This may help. >>>>> >>>>> On Saturday, February 9, 2019 at 2:58:12 AM UTC-6, Dan Hammans wrote: >>>>>> >>>>>> I'm not sure that I understand the difference between the Beagleboard >>>>>> forum and the Beaglebone forum, but thought I would try posting here as >>>>>> well. >>>>>> >>>>>> I have a Beaglebone Blue connected to a GPS module via the GPS micro >>>>>> JST connector. I selected this one because it has +5v, which is what is >>>>>> needed for my GPS as opposed to 3.3v on the other UARTs. >>>>>> >>>>>> The GPS module works correctly, but my issue is I can't power it >>>>>> down. It's been suggested that the 5v rail can't be shut down with the >>>>>> battery connected, but that seems rather odd to me. The also suggested >>>>>> solution was to use a transistor to switch 5v power via a 3.3v GPIO pin. >>>>>> I >>>>>> suppose that's a solution but not a very elegant one if the board can be >>>>>> somehow configured to power off the 5v rail. It seems like this should be >>>>>> possible, albiet not easily accessible. There doesn't seem to be much/any >>>>>> documentation available about this at all. >>>>>> >>>>>> I made a Youtube video showing what's going on; >>>>>> https://www.youtube.com/watch?v=9xrXKRy97Yk >>>>>> >>>>>> Any suggestions appreciated, otherwise I think I'm going to have to >>>>>> go down the path of the transistor relay... >>>>>> >>>>>> >>>>>> -- > 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]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/a081d618-f75a-4343-9fb1-501aec0421a8%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/a081d618-f75a-4343-9fb1-501aec0421a8%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAHabsPQx21c6qerzsSH%3DAnseRi3NSh8oKe0CB0ZxgQUw0Y3NUw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
