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Ghosts II finished

Entry posted by atari2600land December 5, 2017

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About a week and a half ago I wrote about how I finished the first of Ghosts from Nine Inch Nails. Well, a few days after that, I finished Ghosts II. The only song left was 14 Ghosts II. So even though it had a whole bunch of weird noises, I went to work on it and finished it. So I have half the double album done. It only took about 10 years to do. So here's what I have left:
19 Ghosts III, 20 Ghosts III, 23-27 Ghosts III, 29-31 Ghosts IV, 33 Ghosts IV and 35 Ghosts IV. I think I did the longest track first or near first so I wouldn't have to do it later. The longest song out of all those I have left is 4 minutes long.

In case you want to hear these, a few years ago I started a page that I really should update that has all of them on it. http://www.atari2600land.com/ghosts.html
I decided to give up the Killer Snakes project until someone can tell me how I can compare two values in assembly. I can't use SETISAR because the compiler doesn't like it. Before I gave up, I somehow managed to get a piece of fruit on the screen. But this is just too hard for me to do.

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carlsson 26,550

Posted December 6, 2017

I've never studied the F8 instruction set so I'm just guessing. Based on what I can find, it has two compare instructions:

CM: Compare value pointed to by address in (DC0) with the value in the accumulator A, then increase DC0 by 1

CI n: Compare immediate value (constant) n with the value in the accumulator A

I suppose you might want to use the instruction DCI nn to load DC0 with the address to one of the variables you want to compare, then possibly LM to set the accumulator to the value at the address (DC0) points to, then DCI nn again to load the other variable into the register and CM to compare it with the accumulator:

DCI var1

DCI var2

Then you have a good deal of branch instructions to use.