zakqwyThe board needs a thorough de-fluxing, and it's late and I need to go to bed. But I soldered up the other shift register, along with the other components, and plugged the whole works into a USB port that I've got mounted to the underside of my shelving (hence the odd perspective):
This was unexpected behavior. I plugged the Blinkronicator in just to make sure it didn't release the Magic Blue Smoke (tm). When I touched the back of the board (specifically, a few of the programming pads), it started doing weird things as you can see in the video.
What's going on? I'm guessing I'm picking up 60hz from my house's wiring, and that's running through the MOSI pad to SRCLK on the first shift register. Then ... the ATtiny is doing something too? Keep in mind, I just soldered everything together--no code has been uploaded at this point (or written, for that matter).
Anyhoo, it looks like the shift registers are doing something right, and the LEDs are all lighting up (and appear to be different wavelengths), and nothing caught fire. We'll see what happens when I try to control the display...
Discussions
Become a Hackaday.io Member
Create an account to leave a comment. Already have an account? Log In.
You have about 6 more hours....
Are you sure? yes | no
yeah.. Zach ran outta time :-/ but I'm happy with how it turned out! I'll work out a starter program when I get back from Columbus. Also get fresh boards on order so I can scale back the tedium a bit next time..
Are you sure? yes | no
Erm, actually, we extended the deadline.
Are you sure? yes | no
:-)
Are you sure? yes | no
Looks like an open circuit on one of the inputs, probably of one of those shift registers. You see stuff like that when the capacitance of your hand is affecting the voltage of a floating pin.
Are you sure? yes | no
I also noticed that I forgot to install one of the shift registers' bypass caps--I'm sure that doesn't help..
Are you sure? yes | no
right, and an unprogrammed AVR usually results in all pins being inputs without pull-ups, so basically floating. Happy coincidence that it helps with early-early testing :)
Are you sure? yes | no