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30

What is algorithms use for boot/start sound (when turn on computer) Algorithm? Well, yes, technically everything is an algorithm. In this case it's simply executing the beep subroutine during reset, which in turn toggles the speaker line 192 times over 0.1s resulting in a sound of roughly 1 kHz, which should be is close to b′′. Lets have a look into the ...


28

suppose it's possible that the PlayStation audio format does have the required instruments, and then they added the few repeated audio samples on top of that in the game engine There are no instruments "built into" the PlayStation. Games provide their own. The PlayStation sound chip is basically a 24-channel ADPCM playback with 512KB of sample ...


22

Summary: Real Sound Blasters don't need a driver to initialise or support them. Clones may need one-time initialisation. Exotic cards may need memory-resident translation layers. Games use a collection of per-card drivers to 'talk' to the appropriate hardware interfaces. These can be hard-coded into the game, or a collection of external files like in HMI ...


22

Short answer: If you are content with beeps, no. If you want arbitrary sound, yes. There's three ways to get sound out of the PC Speaker: Put the timer chip into square wave mode and send frequencies (actually countdowns) to the timer chip. This is cheap and what's used for most PC Speaker sound effects in games. 140Hz is a popular rate to do it at. Set up ...


19

That paragraph should be understood in the context of the preceding paragraph: The PC speaker was often used in very innovative ways to create the impression of polyphonic music or sound effects within computer games of its era Effects such as those used in Pinball Fantasies in particular involve very rapid changes to the sound output by the PC speaker, ...


16

Most PCI soundcards do not have hardware support for games and other applications that expect a SoundBlaster or AdLib to be present. Older cards made a special effort to provide what's known as "register level compatibility", so they could be used with a wide range of existing games. By the time PCI arrived, Windows had become the PC operating ...


11

They are just timers that can be used for any purpose anyone can think of for keeping track of time in a system. Just like any other timer. The timers can be set to elapse after a certain period of counts, and the status of both timers being elapsed or not can be read from the OPL chip status register. In addition to just reading the status, the timers can ...


11

It's a PSF (Portable Sound Format, see Wikipedia) music file, the PlayStation equivalent of the Amiga's module (.mod) format, where sound samples and replay data sequences are stored inside one file, so tracked music instead of streamed music.


10

The Apple IIgs uses a different routine and has a completely different sound. The monitor entry point is the same as in the Apple //e, though the monitor is a bit tricky to trace because it jumps around a lot (it's trying to preserve the old entry points). To see the code from the Apple IIgs monitor, you need to be in bank $FF. As in the earlier Apple IIs, ...


6

Having multiple graphics or sound chips in a system has exactly the effects you would expect. It would allow the composite system to perform multiple processing tasks at once, with the results of each contributing processor being combined into the final output (or spread across multiple outputs), producing more sophisticated visuals or sounds. Graphics: ...


6

Double-SID mod for Commodore 64 is quite popular. Simultaneous work with CGA and MDA, albeit on different monitors, was also quite popular. Sharp X68000 deserves special attention, taking into account its popular hardware extensions. A classic example of doubling VDP is PC Engine SuperGrafx. Considering the principles of operation of the graphic subsystems ...


6

Here's how the specific routine you posted works. It appears to be using the "4-bit linear" method mentioned on this page. The resulting samples are not truly linear, but it's easy to understand and implement, and good enough for game SFX or speech. We'll analyse this in bottom-up order, starting with the last routine, which simply takes a ...


5

The typical way to provide "driver" services to other programs in DOS is to run a TSR (Terminate and Stay Resident) program installing a software interrupt vector such that running DOS programs could invoke this INT for services (see Ralph Brown's Interrupt List). In the sound context, however, programs would typically do the device I/O directly by ...


5

The BBC Micro uses an SN76489, which provides three tone channels each with sixteen volume levels. For speech playback the standard approach is to set the channels in use to a very high frequency and then modulate the volume. For each channel the volumes are a logarithmic scale, where each step is approximately 10^-0.1 as loud as the previous, i.e. around 79%...


5

The Yamaha Applications Manual (not the Data Sheet) describes how to use the timers and IRQ output. See https://usermanual.wiki/Document/Yamaha20YM381220Application20Manual.26216546/html Sections 3.1.2 and 3.5. Even if the chip signal pins were not connected, one use for the timers was to check if the computer had the chip installed. This Programming Guide ...


5

There are many routine features of a MOD that do not map directly to the IIGS sound hardware — besides the 64kb limit, the Ensoniq also requires samples to be a power-of-two in size and will loop entire samples only. MODs frequently have a loop point somewhere after the start. On the plus side it can trigger an interrupt at the end of any channel's playback ...


4

Like any hardware, the hardware of a sound card needs to be “prepared for operation” after having powered up in an unconfigured state. Usually this consists of writing certain values to certain hardware ports and/or memory addresses (after testing for the presence of said sound card). After this, the sound card is ready for operation. In Windows or any other ...


4

The most accessible Microsoft documentation relating to writing a driver (MS-DOS or otherwise) for the Microsoft Windows Sound System AD-based hardware is MSDN #94396 Windows NT DDK 4.0 Workstation US (01/1997) in the folder /ddk/src/mmedia/sndsys/. It includes a complete reference driver for AD1848-based cards, accessing the ports directly, as expected. It'...


2

Here is an example of what the modern preprocessing Tommy is alluding to actually sounds like: er1.ssd er2.ssd er3.ssd. This is encoded using pcmenc, storing 4-bit volumes for each of the three tone channels in turn, evenly spaced at 35294Hz, so this is 12-bit sampling at 11.7kHz or 4-bit sampling at 35.3kHz depending on how you want to look at it. At an ...


2

Look here for ROM Disassembly: https://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Computers/Apple%20II/Apple%20IIe/Manuals/Apple%20IIe%20Reference%20Manual%20Addendum%20Monitor%20ROM%20Listings.pdf Look on Page 11, Adresses FBD9 to FBEF,


1

When the Sound Blaster was first introduced, the documented way to use the digitized audio features was to make use of a supplied blob of code which was supplied by Creative Labs. If memory serves, using this blob of code required reading it into RAM at a multiple-of-16 address, and invoke it with a normalized form of that address (offset zero of whatever ...


1

Back in the days before the interwebs were the sum of all human knowledge, Microsoft used to supply documentation to MSDN subscribers on funny little plastic discs, affectionately known as 'CDs'. I think sometime around 97 or 98 they published the "Library Archive" as a final, last hurrah, for outdated technical documentation. According to the ...


1

The SB Live series did not include any legacy hardware and support for these were made available with emulation only.


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