Foo - The 7 Segment Led Driver...

Lo and Behold...

http://i301.photobucket.com/albums/nn53/RubenX_Longwood/Other/7-seg-led-drv.jpg

After 3 days and many headaches, the circuit is done.
Inputs A, B, C, and D represent a 4 digits binary number (0110, or decimal 6 on this example).
Yes, I did it myself, didn't copied it from the internets.
It's optimized per led sub-circuit, not per the whole circuit. Some min-terms do repeat, I am aware.
IMHO it's pretty.

Nice work. Have you built the actual unit, or just the diagram?

Nice work. Have you built the actual unit, or just the diagram?

Just the diagram (works on multisim like a charm)... the local Radio Shack doesn't have all the components I need... seems they are more of a toy store now days. Haven't check my local electronics shop tho.

I'm working on a full adder circuit now...

Yeah, the days of Radio Shack being a source of small parts is long gone, unfortunately.

When I was working as an electronics engineer, eons ago, you could buy such things in a single chip pretty cheaply. I have no idea what's available today.

Nice....we all had to go through those pains at one time or another.

I remember taking the VLSI design class where you now went down a level and designed from transistor level. We had to do the receiving side (more complex) side of a UART.

Lo and Behold...

http://i301.photobucket.com/albums/nn53/RubenX_Longwood/Other/7-seg-led-drv.jpg

After 3 days and many headaches, the circuit is done.
Inputs A, B, C, and D represent a 4 digits binary number (0110, or decimal 6 on this example).
Yes, I did it myself, didn't copied it from the internets.
It's optimized per led sub-circuit, not per the whole circuit. Some min-terms do repeat, I am aware.
IMHO it's pretty.

Great derivation! We actually work on 8-segment LEDs in our VHDL class, but the circuit diagram and code are already provided :(

Yeah, the days of Radio Shack being a source of small parts is long gone, unfortunately.

Very long gone. Now they just sell cellphones and r/c cars or something. Now you have to go and find a REAL electronics store.

Just use a decoder. A 74154 should work just fine.

Orcad!!! Nice, now show me the truth tables and the logic :p

Just use a decoder. A 74154 should work just fine.

Who uses TTL any more? That was obsolete when we were using them in college back in the early/mid 90s.

but the circuit diagram and code are already provided :(Well you wouldn't want to create every component from scratch if you were building something bigger. You did your lower class time and learned this stuff, now you need to move on to bigger and better things.


You wouldn't expect a software guy to re-write printf() and other such functions for every program would you? Beginner programmer, maybe so. After that, use the tools and work on bigger products.

So how far can it hit a golf ball?

So how far can it hit a golf ball?

It can announce the "four" for you. :)

He obviously does if he's looking for the components at radioshack. Yeah, you can do that with an FPGA, but what the hell's the point when you'll spend the money three times over just buying a 74154 and some nand gates.

He obviously does if he's looking for the components at radioshack. Yeah, you can do that with an FPGA, but what the hell's the point when you'll spend the money three times over just buying a 74154 and some nand gates.

Does Radio Shack still sell them?

TTL chips? No idea. I haven't been to radioshack in a long time. I go to the electronics store that's been here since at least the 60's.

TTL chips? No idea. I haven't been to radioshack in a long time. I go to the electronics store that's been here since at least the 60's.
That was why I said that. I haven't looked at (or tried to) 'real electronics' at Radio Shack in YEARS. I do recall having trouble finding them (only one or two in area) about 10 or so years ago. I'm guessing you couldn't find them at RS any more, and I figured nobody would sell them any more.

Every CS student has to do the LED thing. You figure out what flicks on what, make your Karnaugh map, then draw your schematic. Its as part of the CS or engineering as prefix, postfix, and infix notation.

I think its a good job.

Sweet!

You're all the way up to 70's technology now. :innocent:

Orcad!!! Nice, now show me the truth tables and the logic :p

Truth table (4 inputs / 7 outputs) and lots of K-maps... that's all I used, I skipped all the Boolean calculations.... can take pic as proof when I get home... :D ... if I remember that is... I'm very sleepy today.

Man you guys are nerds.