Where to go from here?
#1
Hi,
I put a lot of my time into building a simple (no idea how to call it) thing. It is simply an ALU connected to registers and controlled by the ISet. But I have no idea where to go from here. I can write to the ALU, read from it, store the values, program it... But still, how does one make something like GOTO in BASIC (sadly, dead language now. GOTO x jumps onto a line x in a program).

Here is a schematic of the thing I have built:

[Image: Zekcl0K.png]

It is pretty bad image to be honest and I have left out some parts (reset ALU input latches, !A, !B).

Thanks

*(I got the build on a local world)
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#2
Do you have a place where you store your program? If so you would make GOTO using the Program Counter
[Image: dMJ1zUf.gif]
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#3
By 'place to store your program', you mean some kind of rom? I program it directly into the ISet.

But I have stumbled upon two more problems.

Multillication is adding a number to itself x times. So you need three ISet layers and a whole subprogram to run it?

And for the multiplication, you also need to count how many, times did the 'thing' add the number, so how does one compare two values?

Thanks
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#4
Yeah, Multiplication is often either done by an external Math Processor (Somehow attach a Multiplier) or - much more fun - by writing a Multiplication Program, which you need a CPU for and thus branching. Its quite fun to write, actually not that long. However, instead of adding number A  B times to a value C to computate the Result it would be much faster using bit shifting. In that case you actually only have to loop as often as you have bits. For example, to Multiply a 4 Bit with a 4 Bit number to get an 8 Bit result (8 Bit CPU recommended here to avoid major pain in the ass) it would only have to loop 4 times. I wrote such a program for my CPU on build and crammed multiplication into 13 instructions. Ifyou wanna look at it its in the back of my CPU on build. I can definitely show you when im online, which [might?] be in about 7 hours from me posting this.

Hope this helps!
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#5
Thanks, I will try to catch you on.
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