The trouble with self-education ....
Mar. 28th, 2006 09:12 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
tyggerjaiIs that you don't start at the start.
For my electronically inclined readers. One of the things we do at work is hire out big lamps with lampshades. At the moment, they use standard globes. This is so very 20th century, and I've convinced them LEDs would be better. In the first case, a simple R/G/B lamp that can be switched between R, G, and B, with a button, so it's client proof. I know enough to know that what I need here is a shift register, and a momentary button hooked up to the clock line. Easy enough, even debouncing the button. What I *don't* get is how to initialise the shift register. I need something that brings the data-in to the first bit high when the thing is powered up, but never again. I think :) I could presumably do something very complex that brings the first bit high if none of the other bits are high, but that seems ... complex. Is there something hinky with capacitors or transistors that everyone who actually knows about this stuff already knows about? It seems like electronics 101, but the web seems unhelpful.
[Update: Hm. http://www.play-hookey.com/digital/experiments/rtl_monostable.html looks promising. It's almost as complex as the rest of the circuit, but never mind :)]
sol.
.
For my electronically inclined readers. One of the things we do at work is hire out big lamps with lampshades. At the moment, they use standard globes. This is so very 20th century, and I've convinced them LEDs would be better. In the first case, a simple R/G/B lamp that can be switched between R, G, and B, with a button, so it's client proof. I know enough to know that what I need here is a shift register, and a momentary button hooked up to the clock line. Easy enough, even debouncing the button. What I *don't* get is how to initialise the shift register. I need something that brings the data-in to the first bit high when the thing is powered up, but never again. I think :) I could presumably do something very complex that brings the first bit high if none of the other bits are high, but that seems ... complex. Is there something hinky with capacitors or transistors that everyone who actually knows about this stuff already knows about? It seems like electronics 101, but the web seems unhelpful.
[Update: Hm. http://www.play-hookey.com/digital/experiments/rtl_monostable.html looks promising. It's almost as complex as the rest of the circuit, but never mind :)]
sol.
.