Noway2 said:
You do realize that this is almost cerainly a project assignment for
school.
I can't think of any other reason why somebody would attempt to do this
discrete logic unless they were trying to enforce combinational and
sequential logic design.
Personally, I am getting really tired of reading "Please Send Me" from
everybody that want to be handed a design for their homework. When I
was in school, I would have been delighted just to have a usenet group
to be able to get hints from.
Yup. Probably not a direct assignment, more like a "choose your own
project". No teacher would ask students to do something like this
directly. Not only that, but this is going to be expensive.
Mr. Kupal has a couple of options, as I see it. He can go back to his
teacher and ask for another project, because this one is gonna be
"acres o' digital". One possibility more within the reach of a novice
electronics student would be getting one 16-segment alphanumeric LED
display, and then scrolling the letters at one per second, with two
blanks after the word. Still a bit of '70s digital logic, but very
doable, especially if he's allowed a couple of PROMs. And within a
student's budget, too.
Second, he can find a copy of Don Lancaster's TV Typewriter Cookbook
(Mr. Lancaster will be more than willing to send a copy
http://www.tinaja.com/books/bkdons.asp ) and look for hints as to how
to do something like this. I'd figure he's doomed unless he can use an
EPROM at least to store the data, then he can probably use a triple
counter (one for multiplexing, one for data, and another for data start
position) to achieve the scrolling effect. Not easy. There's a good
reason why these things didn't exist before microcontrollers.
The third option is to utilize this newsgroup as the OP says -- you do
the work, and send him the bill. Ask for cash in advance.
Good luck
Chris