These days, wouldn't you just plop a Z80 core into an FPGA or >whatever?
[....]
I am also old enough to have worked on the design of bit slice
computers, printed out my listings on a teletype, input my code on
paper tape, and write programs on punch cards that were sent away to
the computer.[...]
You ain't the only one. Never got to build my bit slice machine
though. Strange, it influenced the design of many machines along the
way.*my* bit slice didn't get built. Somebody else's did. I also
consulted to someone building a 3rd one that I can't go into.I also did a machine that was a lot like a bit slice that didn't
really have an ALU. It was a system that needed to read a bunch of
bytes from memory and rearrange the nibbles quickly. The idea of
using a registered PROM and a counter to make logic signals has popped
up many times.
Ahhh. Primitive state machines. Another useful tool that has been
around a while. Some of the current tools for state machines help you
set up multiple interacting state machines. Now that can be fun.
The project I am working on has multiple state machines in the micro.
They still make a great way to arrange the problem to be solved.
Some years back, these guys showed up trying to sell a state machine
based product development tool for products. It was a very clever
scam. Among their claims was that their product output C code that
was 100% if your design was correct in their tool. When I got into
the details, I discovered that to develop you wrote stuff like:
if (some expression) tra-la-tra-la {
Some code to do tra-la-tra-la
}
they then ran using that code. When it came time to output, they just
had to strip out the "tra-la-tra-la". I spent a weekend and made a
more useful tool. Their's required you to basically write your
application before you could show what it did to marketing. Mine made
a very quick fake up of the user interface with a lot less code.
These days, wouldn't you just plop a Z80 core into an FPGA or whatever?
Cheers!
Rich
[....]
I am also old enough to have worked on the design of bit slice
computers, printed out my listings on a teletype, input my code on
paper tape, and write programs on punch cards that were sent away to
the computer.
[...]
You ain't the only one. Never got to build my bit slice machine
though. Strange, it influenced the design of many machines alongthe
way.
*my* bit slice didn't get built. Somebody else's did. I also
consulted to someone building a 3rd one that I can't go into.
I also did a machine that was a lot like a bit slice that didn't
really have an ALU. It was a system that needed to read a bunch of
bytes from memory and rearrange the nibbles quickly. The idea of
using a registered PROM and a counter to make logic signals has popped
up many times.
Ahhh. Primitive state machines. Another useful tool that has been
around a while. Some of the current tools for state machines help you
set up multiple interacting state machines. Now that can be fun.The project I am working on has multiple state machines in the micro.
They still make a great way to arrange the problem to be solved.Some years back, these guys showed up trying to sell a state machine
based product development tool for products. It was a very clever
scam. Among their claims was that their product output C code that
was 100% if your design was correct in their tool. When I got into
the details, I discovered that to develop you wrote stuff like:if (some expression) tra-la-tra-la {
Some code to do tra-la-tra-la
}they then ran using that code. When it came time to output, they just
had to strip out the "tra-la-tra-la". I spent a weekend and made a
more useful tool. Their's required you to basically write your
application before you could show what it did to marketing. Mine made
a very quick fake up of the user interface with a lot less code.
Variations of Dan Bricklin's "Demo" program of old in there somewhere?
[....]
I am also old enough to have worked on the design of bit slice
computers, printed out my listings on a teletype, input my code on
paper tape, and write programs on punch cards that were sent away to
the computer.[...]
You ain't the only one. Never got to build my bit slice machine
though. Strange, it influenced the design of many machines along the
way.*my* bit slice didn't get built. Somebody else's did. I also
consulted to someone building a 3rd one that I can't go into.I also did a machine that was a lot like a bit slice that didn't
really have an ALU. It was a system that needed to read a bunch of
bytes from memory and rearrange the nibbles quickly. The idea of
using a registered PROM and a counter to make logic signals has popped
up many times.Ahhh. Primitive state machines. Another useful tool that has been
around a while. Some of the current tools for state machines help you
set up multiple interacting state machines. Now that can be fun.The project I am working on has multiple state machines in the micro.
They still make a great way to arrange the problem to be solved.Some years back, these guys showed up trying to sell a state machine
based product development tool for products. It was a very clever
scam. Among their claims was that their product output C code that
was 100% if your design was correct in their tool. When I got into
the details, I discovered that to develop you wrote stuff like:if (some expression) tra-la-tra-la {
Some code to do tra-la-tra-la
}they then ran using that code. When it came time to output, they just
had to strip out the "tra-la-tra-la". I spent a weekend and made a
more useful tool. Their's required you to basically write your
application before you could show what it did to marketing. Mine made
a very quick fake up of the user interface with a lot less code.
Variations of Dan Bricklin's "Demo" program of old in there somewhere?
No, it was a very simple program hunked together from code I had
written for other purposes and some new code. Basically it took in
some simple ASCII files and made a picture on the screen that you
could then click on.
The first file described the outline of the front panel, the outline
of the display and the outlines of all of the buttons. The graphics
was done with a palette so that each button was a "different color"
even if the colors were the same. This let me easily know which
button the cursor was over.
The second file contained a list of all the states in the form of:
STATE StateName
ON Button1 OtherState
ON Button2 DifferentState
Text X Y "Hi there the power is now on"
END
There were some special cases like the position an nature of the
cursor that had their own keywords.
I might do that, or a different core, or no core at all, or an external
micro, or something different. Depends on what i conclude the is right
solution to the task / problem / opportunity at hand.
BTW: The term chad got attached because a guy named Chadless invented
one that only cut 3 sided and folded the bit of paper over. People
mistook it for being a name for one that doesn't make chad and thuse
the little bits must be chad.
That's a myth promoted by older versions of the jargon file
(current versionhttp://catb.org/esr/jargon) and sundry others.
