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IBM PS/1 Audio Card.

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Reply 41 of 87, by Cloudschatze

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jmk wrote:

Silpheed (PS/1 Version) - Reported OK.

Should someone happen upon this thread who actually owns this version of Silpheed, can you please send me a PM? I would very much like to know if the DAC support is PS/1 audio-card specific, or if another DAC driver can be used (Sound Blaster, Tandy DAC), as with other Sierra games.

Reply 42 of 87, by Great Hierophant

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Myloch wrote:

there is an inaccuracy in the gamelist: King's quest 5 also uses DAC, start a game and go 2 or 3 screens to the west (where there are the gypsies) and wait, you'll hear a cow bellow sometimes.

Actually, I do not think the cow bellow sound effect is a digital effect but an FM effect, because it can be heard using the Adlib driver as well as the Sound Blaster driver. I cannot hear the cow bellow using either the PS/1 Audiocard or Tandy TL/SL/RL driver.

http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog

Reply 43 of 87, by DistWave

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jmk wrote:

"if the silver part marked 143NDK1X (near the 34-pin connector) is a 14.318180 Mhz crystal and we divide that by 4 to get the most likely master clock... then it would be 3.579545 Mhz."

Of course, that is making an assumption, since I can't follow the tracks directly into the 34-pin connector.

The 34 pin header where the PS/1 Audio Card plugs provides a clock signal, but it is not 14.318 MHz. I built a OPL3 FM sound card for this machine and I tried to use this clock signal to feed the OPL3 but the sound generated was in a low pitch that expected. I had to use a dedicated 14.318 oscillator for it.

- The first IBM PS/1 (model 2011, based on a 286 processor) runs at 10 MHz.
- Looking at the Myloch photo, there is a 10 MHz oscillator next to the 34 pin header.

I bet that this is the frequency provided to the sound card.

Reply 44 of 87, by Great Hierophant

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The Texas Instruments SN76496 (IBM PCjr., Tandy 1000/A/HD/EX), clone (Tandy 1000 SX/HX/TX) or integrated (Tandy TL/SL/RL/RLX/RSX series) series use a base frequency of 3.579MHz. If the PS/1 Audio Card does not have an oscillator that is a multiple of that frequency on its board or sent through the pin header, then it is highly unlikely to sound the same as one of the above chips.

If we assume that the only clock signal being fed to the chip is the 10MHz signal, then the base frequency for the 3-voice generator is likely to be either 5MHz, 3.33MHz or 2MHz, since frequency dividers are almost always integer in function. The middle figure is only 7% from the "ideal" exemplar given above, but divide by 3 frequency dividers require more die space on a VLSI chip than divide by 2 or 4 frequency dividers.

http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog

Reply 47 of 87, by Great Hierophant

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This video I found seems to indicate that the frequency of the IBM card is probably exactly the same as, or very close to the Tandy chip.

http://www.youtube.com/watch?v=zrwhlRSixjI

The user is playing Silpheed on an IBM PS/1 Model 2011 with a real IBM PS/1 Audio/Game Card. The pitch between the music from the Tandy and the PS/1 drivers does not sound noticeably different (at least differences which cannot be explained by the video's audio.

Since IBM designed the original PCjr, they would have had full technical knowledge of how the sound worked, and as they must have seen how the Tandy machines took that chip and made a successful line of computers, I think IBM would have indirectly taken inspiration from itself to manufacture a low-cost (but overpriced) audio and game solution for its PS/1.

http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog

Reply 48 of 87, by mastercontrol90

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I, im the owner of silpheed video, i'm glad to se that my video helps you a little bit in ps/1 sound emulation. If you want i can make other videos (well made not like the first, with direct line sound recording), just reply with a list of compatible games with this hardware and i'll find them.

PS: rtc chip is dead (witouth that floppy drive don't work) and i've to replace it, i don't want to mod, i always have the fear that this pc dies (in fact im interested in replacement parts for ps/1 2011)

Reply 49 of 87, by Great Hierophant

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mastercontrol90 wrote:

I, im the owner of silpheed video, i'm glad to se that my video helps you a little bit in ps/1 sound emulation. If you want i can make other videos (well made not like the first, with direct line sound recording), just reply with a list of compatible games with this hardware and i'll find them.

PS: rtc chip is dead (witouth that floppy drive don't work) and i've to replace it, i don't want to mod, i always have the fear that this pc dies (in fact im interested in replacement parts for ps/1 2011)

It isn't too hard to fix that RTC so you won't have to replace it :

http://www.mcamafia.de/mcapage0/dsrework.htm

http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog

Reply 50 of 87, by mastercontrol90

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ok i will fix that when summer ends (in this days we have from 38 to 44 C') i don't want to make my ps1 going hot and burn. Meanwhile give me a list of compatible games if you want to hear them on real hardware and when i can i will record them for you 😉

Reply 52 of 87, by Myloch

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Great Hierophant wrote:

This video I found seems to indicate that the frequency of the IBM card is probably exactly the same as, or very close to the Tandy chip.

http://www.youtube.com/watch?v=zrwhlRSixjI

The user is playing Silpheed on an IBM PS/1 Model 2011 with a real IBM PS/1 Audio/Game Card. The pitch between the music from the Tandy and the PS/1 drivers does not sound noticeably different (at least differences which cannot be explained by the video's audio.

yeah emulation is very good but am I the only one to find a real difference between the emulated thing and the real thing? Nice to see this argument raising again because I was the one who felt that the pitch was quite off (with the real thing being a bit higher with the pitch). You can easily notice it if you capture audio from the intro and you compare it with the one from the video.
I use the dosbox build made by yhkwong.

Maybe mastercontrol90 can grab the audio directly from the ps1 audio jack or something like that and compare it with a dosbox wav capture like this in the attachment.

Attachments

  • Filename
    sierra_002.rar
    File size
    1.4 MiB
    Downloads
    176 downloads
    File license
    Fair use/fair dealing exception

Reply 53 of 87, by mastercontrol90

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YEP I CAN!!! finally all the bad wheater full of lightning is away so i can turn on the ps/1 2011

here it is a record directrly from headphones out, there is a little static noise, both from the ps1 and the shitty cable but the recording is good

EDIT: NOW is attached sorry for the wait 🤣

PS: at the end i replaced the rtc battery with a 12887

Attachments

  • Filename
    silp rec ps1.zip
    File size
    1.99 MiB
    Downloads
    186 downloads
    File license
    Fair use/fair dealing exception

Reply 56 of 87, by Myloch

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the ps1 audio emulation is based heavily on the source code of the tandy emulation, so this is the reason why it sounds exactly the same.

The real ps1 audio card however is not exactly the same thing as a tandy hardware. 😉
(the different pitch)

Reply 57 of 87, by Great Hierophant

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I have attached a DOSBox recording of the first level of Silpheed using the Tandy sound driver. It helps to compare the same tracks. I am still finding it difficult to distinguish this sound from the sound recorded by mastercontrol90 two apart from the filtering and amplification of the analog recording.

DistWave reports that he needed to put his own crystal on his homebrew Adlib PS/1 clone because the clock coming from the motherboard was giving too low a pitch. The Adlib and Tandy chips use the same base frequency. If the PS/1 Audio card takes its clock signal from the motherboard, it would have a lower pitch as well. Perhaps Sierra increased the tempo of the music to compensate in the PS/1 release.

I was too lazy to make a recording of the music from my actual Tandy.

Attachments

  • Filename
    sierra_000.zip
    File size
    2.06 MiB
    Downloads
    141 downloads
    File license
    Fair use/fair dealing exception

http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog

Reply 59 of 87, by Myloch

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Obviously I can't be 100% sure (I don't have the original machine anymore) but I clearly remember other games like Bushbuck had higher pitch on original Ps/1 compared to actual ps/1 emulation, not only Silpheed by Sierra.