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jotego / jt12

FM sound source written in Verilog, fully compatible with YM2612, YM3438 (JT12), YM2203 (JT03) and YM2610 (JT10)
GNU General Public License v3.0
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Fix timer length #43

Closed greyrogue closed 4 years ago

greyrogue commented 4 years ago

--Looks like a simple off by one error int the timer length. --Fixes Genesis Konami speed issues.

jotego commented 4 years ago

Thanks a lot @greyrogue Now that it's merged, I will replace the comparison: mult+1'b1<mult_max with a less or equal comparison without addition: mult <= mult_max which probably synthesizes in a bit less area.

greyrogue commented 4 years ago

I think that moves it the wrong way. Instead of 0-23, you get a range of 0-25 with mult<=mult_max. Maybe the cleaner way is to keep mult<mult_max, and change mult_max to 23 (and 383 for timer B).

greyrogue commented 4 years ago

I had used mult+1'b1 because the same expression appears two lines lower. A smart compiler would notice they are the same and only implement it once in logic. But I think using 23 and 383 might be the better way to handle it, as those are actually the max values.