After posting on Stack Exchange to help solve my dilemma, somebody nudged me in the right direction. I was using different grounds because the Arduino was being powered by the 5v from the USB. Once I connected the Arduino to the 5v rail and let it get it's power there, everything was happy.
All the simulated testing works fine, meaning when I toggle off the 3.3v line, the transistor turns off, and the LED goes out. However, when I drop the same setup onto a circuit board, the LED comes on and stays on, even when the Arduino pin is LOW.
I even discovered with the Arduino out of the circuit, simply touching what would be the 3.3v line resulted in the LED lighting up, albeit rather dimly.
I'm sure I'm missing something stupid. Everything I've read says this should work.
Anybody do much work with electronics, or have a decent understanding of NPN transistors? Bashing my head on what should be a simple circuit, and it's not behaving right.
Basically using an 2N2222 NPN transistor as a switch, base is connected to digital out pin on an Arduino at 3.3v and a 10k resistor. Collector is connected to 5v, a 330 ohm resistor, and an LED. And the emitter is connected to ground.
I was doing some tinkering this weekend with one of my Raspberry Pi devices, setting it up for some ham radio ops. Added an RTC but needed to make custom jumper cables. DuPont connectors are a pain to put together, and it really helps if you have the right tool, one that is "close enough" just messed up the crimps.
Also need to think about a custom case, still need to squeeze a buck converter in there too.
heads up if you ever use gimp for redacting screenshots and the like
with the default settings, "clear", or the delete key, only makes a region transparent but doesn't delete the colour info. it can easily be retrieved
ways to fix this are:
1. uncheck "save colour values from transparent pixels" when exporting
2. put a fresh transparent layer underneath everything, its colour info (pure black) will be saved instead
3. just fill the area with a solid colour instead
3.1. or save as jpeg
Fun random thought popped into my head. In my haste, ages ago, in turning on MFA for lots of accounts I realized I created a circular dependency. If I lose my phone, I can't get into my Google account because I have the password in a password manager, that is protected by Google's Authenticator. Ooops. How does everybody else protect their accounts without creating circular dependencies? #security #mfa #2fa
OK, I stood up a rudimentary bot to pull the RSS feed from the US NOAA National Hurricane Center. You can find it at @HurricaneBot
I don't normally ask for such things, but I'd appreciate a boost on this one. Hopefully it will be a help to someone.
The year is 2073. All proprietary social networks are dead. Microsoft and Intel are long gone, everyone uses locally-fabbed RISC-V chips. The world has been cured of cancer, politics and electron.
There are no remaining hardcopy records of the half a century leading up to this, because nobody could get their printer drivers working in that entire time.
Do you suffer from mental health crises? A few years ago a friend floated the idea of an app that might help people cope. I've finally started putting together a prototype and would like a few people on standby to try it out. If you have an android phone, are in the UK and would be interested, please send me a direct message.
Food is happening...
Food is happening...
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