Photon not supplying power

I am able to turn on d7 LED on my board to ensure it is receiving signals from my phone. Unfortunately i am unable to power my breadboard with the Vin and Ground. I am using a 74ls47 connected to d0-3 to control a 7-segment display. I tested each of the nodes with a logic probe, not getting logic high or low, when i set d0-3 high

You are powering the Photon via USB?
What USB supply are you using?
Can you post your code?
Have you got some schematics of your setup?

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I am using a USB to power the board, I have no code, i am sending the logic signals in tinker mode. I currently do not have access to multisim. I have isolated the 74ls47 and 7-segment. They are working perfectly. The only probelm is the power supply from the vin from the photon, and the d0-3 i am using for logic levels are not outputting the correct levels.

And how much current can you draw from it?
Is it a computer port or a USB power supply?
How much amperage is it rated?

Do you mean they are not delivering 5V (which is expected with a 3.3V device) or do the pins not even provide the 3.3V when set to HIGH?

When powered off of a 5V USB supply, you should see ~4.8V on Vin but any GPIO will only ever source max. 3.3V when set to OUTPUT HIGH.

@Conasty, which “logic probe” are you using? It may be picky about the voltage it needs to see to call it a “HIGH”. It would be better to use a multimeter to measure the actual voltage at the GPIO pins.

I am using a Computer USB port, When i set d0 to high in tinker mode, and check the logic level of d0. My probe tells me that is is not high or low. I do not have a multi meter at my home, so i am unable to check the exact volt level or amp in each of the nodes. This project is being done by 10 other people in my class, so i would assume it is not the volt or amp shorten required by my components. @peekay123 that may be the case that my logic probe is having trouble giving me a accurate reading, but the board is still not receiving any power from the vin of the photon, which is my main problem.

@Conasty, there is a protection diode between Vusb and Vin. If that diode is damaged, it may be “open circuit”, providing no voltage on Vin. Again, which logic probe are you using??

Elenco model LP-560

For measuring the GPIO, set it to"CMOS". You should see a “HIGH” on the Vin pin with a TTL setting.

when i set it to CMOS&TTL and measure the vin pin, it reads High and low. Which i would assume is open, but i can not find that option on the reading guide of my probe.

@Conasty, you need a multimeter to go any further unfortunately.

I can head to my college to finish the troubleshooting. I will have access to a multi meter, oscillator, and a function generator. What should i do at this point?

Measure the voltage between the GND and Vin pins of the Photon and report back your findings.

Ok should have a response in roughly 1 and a half hours.

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After testing the vin with a multi, it is giving 4.8V. The circuit is working now. I had to do another claiming process, and discovered that I ordered a new photon, but received a use one named pizza_raptor.

How do you know it was used? And where did you get it from?

Amazon, and it had a name that I did not assign it.

As it so happens, when devices are created, they are auto-generated names, so it is possible the device is, in fact, new.

If the device was shrinkwrapped and did not have any blockers claiming it was currently claimed when attempting to claim it, it is likely that it is new.


And sometimes very funny names… I’ve kept the names on several occasions just for laughs.

That’s exactly why I asked.

The auto-generated names can be hilarious. I have captain-ferret (my favorite), calm-dentist,and narwhal-monkey on hand.

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