Re: A DOS program to test OPL2 percussion (0xBD)

Posted on 2022-05-12, 21:57

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by Electronic Genets

in PC Emulation

in PC Emulation

I am looking for bug and I cannot find it. Is it possible that DOSBOX wrongly record (I use DRO dump) the B7 and A7 registers in percussion mode? The value of B7: A7 = 0005 is strangely small. It is impossible to get 200 Hz from FNum=5 and Block=0. Settings of B7 and A7 registers checked manually. …

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Re: A DOS program to test OPL2 percussion (0xBD)

Posted on 2022-05-12, 13:11

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by Electronic Genets

in PC Emulation

in PC Emulation

the snare drum is missing the square wave that is typically mixed in with the (fixed frequency) noise. OPLx , thank you for the answer. I will check it, but I in flight resample from 49716 to 32000 (in drum mode 2 channels partially operate at 49716 Hz - phase generator of operators 13 and 17 works …

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Re: Drums on truly real OPL2

Posted on 2022-05-12, 08:35

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by Electronic Genets

in PC Emulation

in PC Emulation

Copyright (C) 2019 - 2021 Superfury This file is part of UniPCemu. UniPCemu is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later …

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 23:15

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by Electronic Genets

in PC Emulation

in PC Emulation

Probably if the format is converted from 10.10 to 16.16 the integer must be multiplied by 1<<6 = 64. But I don't see the point in shifting it 6. FREQ_SH might be 10 instead 16 without it.

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 21:42

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by Electronic Genets

in PC Emulation

in PC Emulation

I don't know and I don't find the equivalent in my code.

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 21:19

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by Electronic Genets

in PC Emulation

in PC Emulation

superfury wrote on 2022-05-11, 21:17: Would the changing of 64 to (1/169) in the fnum lookup table be correct in this case (see my reverse calculations of 1Hz using octave 0)? Can you please tell me what 64? Where does 64 come from?

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 21:02

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by Electronic Genets

in PC Emulation

in PC Emulation

Read also about Floating point Patriot problem. Such are the long-term effects of using floating point numbers. There is no error for a few seconds and then it can grow. FIXED-point should be used if it is possible.

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 20:40

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by Electronic Genets

in PC Emulation

in PC Emulation

FREQ_SH - part of emulators uses 10.10 fixed point accurancy (FREQ_SH=10). Part uses 16.16 (opl3Emu: FREQ_SH=16). I use 10.22 because on 32-bit register (STM32) because I can remove the "and" after shifting right by 22 positions (time critical section) - FREQ_SH=22. If you use 10.10 format, you will …

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 17:59

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by Electronic Genets

in PC Emulation

in PC Emulation

superfury wrote: So the increase is (frq<

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 16:52

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by Electronic Genets

in PC Emulation

in PC Emulation

Superfury , look at opl3emu and nukedOPL3. I use format 10.22 in the DINO-2e OPL-2 like emulator. In this case the floating point operations are not needed. Yamaha also doesn't need them and Yamaha doesn't need multiplying (all done by fixed point addition, xor, and, or, shifts and arrays). f - …

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 16:36

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by Electronic Genets

in PC Emulation

in PC Emulation

Superfury Probably your result in range <0, 1) should be multiplied by 1024 and then extract these bits. But variable-point formats are inaccurate.

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Re: Control F10

Posted on 2022-05-11, 15:38

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by Electronic Genets

in DOSBox General

in DOSBox General

"Guys" in English is commonly used as a gender-neutral term. https://www.washingtonpost.com/outlook/2021/07/07/guys-defense-gendered-etymology/ https://en.wiktionary.org/wiki/guy#Usage_notes In plural, guys may not be completely gender-neutral , but it may refer to people of any gender in some …

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Re: Control F10

Posted on 2022-05-11, 13:47

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by Electronic Genets

in DOSBox General

in DOSBox General

Hi Guys, I am a woman, not guy. I really don't like it when people think that all programmers and all electronics are boys. "Hi colleagues" or "Hi to all" will be more appropriate... But it is completely unnecessary on forums and chats. In the config file i had: mapperfile=mapper-0.74.map while it …

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 10:53

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by Electronic Genets

in PC Emulation

in PC Emulation

Although I don't know how to calculate the frequency shifts in fixed point format. Do you mean bit2, bit3, bit5 and bit7? If yes, it is very easy. // phaseCounter is in format 10.22 fixed point uint32_t phaseCounter uint16_t tmp=phaseCounter>>22; // normalize to 10-bit integer uint8_t bit2=(tmp …

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Re: Drums on truly real OPL2

Posted on 2022-05-11, 08:33

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by Electronic Genets

in PC Emulation

in PC Emulation

and forth between the floating point format of the modulator/carrier output Due to loss of accuracy of floating point numbers at each operation you should not use them to calculate phase of drum (HH, TC, SD) instruments. If your value 16384 will be rounded to 16383.997 your output of HH and TC will …

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Re: Control F10

Posted on 2022-05-10, 22:50

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by Electronic Genets

in DOSBox General

in DOSBox General

Try to hit "0" (zero) key on keyboard if you see red alert and skip point 7. We probably use different versions of DosBox. Before next -startmapper use -resetmapper because I don't know what happened after point 6). Keymapper in DosBox is very non-intuitive. White box means: checked Black box means …

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Re: A DOS program to test OPL2 percussion (0xBD)

Posted on 2022-05-10, 20:59

by

by Electronic Genets

in PC Emulation

in PC Emulation

OPLx, can you please check these VGZ tracks sound similar to original OPL2 or OPL3? I think about percussion. It is dumped to DRO format and then played at 32kHz with WAV recording by my DINO-2e library.

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Re: Drums on truly real OPL2

Posted on 2022-05-09, 23:44

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by Electronic Genets

in PC Emulation

in PC Emulation

These are sampled at that rate, then lowpass filtered at 15392Hz. I see you also cannot hear this feedback squeak that makes all music uncomfortable. I cut it with special algorithm for feedback (only if OPL_FREQ is set to 49716 the filter is disabled for full compatibility). Don't compare game …

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Re: Control F10

Posted on 2022-05-09, 21:40

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by Electronic Genets

in DOSBox General

in DOSBox General

Thanks for your reply. Will you be so kind to tell me the correct procedure? 1) Run dosbox with parameter -setmapper dosbox -setmapper 2) Click "Cap Mouse" 3) Click "Next" until you see "Bind: Ctrl F10" 4) Click "Del" 5) Click "Add" 6) Click "0" (zero) 7) Click "Cap Mouse" 8 ) Check Mod1 and Mod2 ( …

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Re: Drums on truly real OPL2

Posted on 2022-05-09, 19:52

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by Electronic Genets

in PC Emulation

in PC Emulation

tempphase <<= 9; //0x200 when 1 makes it become 0x300 tempphase |= 0x100; //0x100 is always! tempop_phase = phase8_2; //Calculate the phase of channel 8 carrier signal! if (((tempop_phase>>3)^(tempop_phase>>5))&1) tempphase = 0x300; result = calcOperator(8, op8_2,op8_2,op8_2, adlibfreq(op8_2), …

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