IBM PS/1 Audio Card.

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Re: IBM PS/1 Audio Card.

Postby Mau1wurf1977 » 2011-3-31 @ 12:01

wd wrote:

Did you already start working on it?[/quote]

Yup, just need good programmers to join the project.
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Re: IBM PS/1 Audio Card.

Postby Cloudschatze » 2011-5-26 @ 02:08

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.
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Re: IBM PS/1 Audio Card.

Postby Great Hierophant » 2011-7-01 @ 05:02

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.
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Re: IBM PS/1 Audio Card.

Postby DistWave » 2011-8-15 @ 18:17

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.
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Re: IBM PS/1 Audio Card.

Postby Great Hierophant » 2011-8-16 @ 06:06

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.
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Re: IBM PS/1 Audio Card.

Postby Adgarharrison » 2011-9-14 @ 09:06

1987 Tandy 1000 HX. Finally gave up the ghost in 2002. Would probably still work if it hadn't been exposed to moisture, which corroded the motherboard. :lol:
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Re: IBM PS/1 Audio Card.

Postby fjk61011 » 2012-4-09 @ 11:59

I was going to buy a PS/1 Audio Card in Canada but opted for aSoundBlaster only to discover my PS/1 had no ISA slots. This was in 1993
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Re: IBM PS/1 Audio Card.

Postby Great Hierophant » 2012-5-01 @ 13:36

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.
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Re: IBM PS/1 Audio Card.

Postby mastercontrol90 » 2012-6-15 @ 09:22

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)
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Re: IBM PS/1 Audio Card.

Postby Great Hierophant » 2012-6-15 @ 18:38

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
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Re: IBM PS/1 Audio Card.

Postby mastercontrol90 » 2012-7-19 @ 12:28

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 ;)
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Re: IBM PS/1 Audio Card.

Postby mastercontrol90 » 2012-8-30 @ 08:35

OK, i replace it with a ds12887 that "someone" give to me XD and i repaired the joystick
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Re: IBM PS/1 Audio Card.

Postby Myloch » 2013-1-24 @ 15:22

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.
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sierra_002.rar
(1.4 MiB) Downloaded 145 times
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Re: IBM PS/1 Audio Card.

Postby mastercontrol90 » 2013-3-04 @ 15:48

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 XD

PS: at the end i replaced the rtc battery with a 12887
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silp rec ps1.zip
(1.99 MiB) Downloaded 158 times
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Re: IBM PS/1 Audio Card.

Postby Myloch » 2013-3-04 @ 16:53

nice recording, it can be useful for the forumers. thanks man!

this is the final proof my theory was correct, the pitch of the real thing is higher than the emulated thing.
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Re: IBM PS/1 Audio Card.

Postby mastercontrol90 » 2013-3-04 @ 16:55

yup! i confirm that... the emulated one sounds EXACTLY like the tandy one and this is just wrong
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Re: IBM PS/1 Audio Card.

Postby Myloch » 2013-3-04 @ 16:58

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)
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Re: IBM PS/1 Audio Card.

Postby Great Hierophant » 2013-3-19 @ 13:48

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.
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sierra_000.zip
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Re: IBM PS/1 Audio Card.

Postby VileRancour » 2013-3-19 @ 19:44

That is slightly more than a full step lower in pitch than the PS/1 recording.
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Re: IBM PS/1 Audio Card.

Postby Myloch » 2013-3-21 @ 16:19

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.
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