druzyek

4 ms·

1.
by druzyek 5y ago
The BCD processing was indeed a big advantage of the V20, which is why Casio used it in graphing calculators like the AFX 1.0 and 2.0. One point about comparing to the 8087 is that the 18-digit packed BCD format the 8087 used was converted
2.
by druzyek 6y ago
> The best approach is to write your definitions the way you like, mostly ignoring speed and cycles and byte count. This should result in clean, elegant definitions. This first step reveals some short words like your @+1 that could be go
3.
by druzyek 6y ago
> I believe you are victim of premature optimization. You knew Forth would be slow because interpreted, so you feared for performance. Fear often makes you do the wrong things. As I explain on the page, the Forth I'm using is not in
4.
by druzyek 6y ago
Hi astrobe_, interesting points! I disagree with you on a few things: > Looking at the C version, the argument "tile" is used once in the function, to get the pointer to the tile. The pointer could be passed directly: one less
5.
by druzyek 6y ago
PLASMA is a really neat project! I considered it and a few other systems before settling on C, assembly and Forth. Ultimately I left it out because I was focusing on performance not size, so a byte-code VM would not be a good fit.
6.
by druzyek 6y ago
Right, I do this in the assembly versions everywhere I multiply by a constant. mult5 is just an example.
7.
by druzyek 6y ago
OP here. This is a really interesting point. My strategy was to keep the highest level functions/words like DrawTile or DrawMenu while writing the underlying Forth and subwords from scratch focusing on performance. Do you have any sugg
8.
Robot Game: Comparing 6502 C, Assembly, and Forth(calc6502.com)
94 points by druzyek 6y ago|35 comments
9.
Robot Game: Comparing 6502 C, Assembly, and Forth(calc6502.com)
2 points by druzyek 6y ago|0 comments
10.
by druzyek 7y ago
This article is specific to the 6502 where the commonly used CC65 C compiler the author references produces much, much worse code speed wise than what you can with pure assembly. In that regard, the article is not simplistic in the least. C