BloodyCactus wrote on 2021-09-15, 00:23:

oh yeah there is also RaSCSI which can do ISO emus and its a PI so you remote in and tell it which iso in the config, or it usees a browser for config so its easier.

But that doesn't support CD audio does it? That's the whole problem. We need something for DOS that supports bin/cue and will play CD audio.

The $200 unit covers that for IDE and the MAC SCSI one that is $120 does as well but the MAC one sounds like it is not nearly as easy to use as the images are configured through an .INI file.

@SmooBandit. Thank you for your feedback. I followed the debugging series of the IDE Simulator. A hard work has been done on it.

There was a similar attempt by Zorix called the Z-IDE, but seems abandoned.

cyclone3d wrote on 2021-09-15, 00:58:

BloodyCactus wrote on 2021-09-15, 00:23:

oh yeah there is also RaSCSI which can do ISO emus and its a PI so you remote in and tell it which iso in the config, or it usees a browser for config so its easier.

But that doesn't support CD audio does it? That's the whole problem. We need something for DOS that supports bin/cue and will play CD audio.

The $200 unit covers that for IDE and the MAC SCSI one that is $120 does as well but the MAC one sounds like it is not nearly as easy to use as the images are configured through an .INI file.

Audio output needed. And not only for DOS, but for Windows 3.x (well, MCI depends on the DOS CD extensions) and Windows 9x too.

All virtual CD-ROM drives I know only works from Windows 95 OSR2 (build ≥ 4.00.1111), none for 4.00.950. And from my experience, analogue audio emulation uses a few resources (PCM conversion, redirections to a driver, managing a buffer etc), on 486 and on first gen Pentium it can be a little problematic. Comes the network problem too. A CD image is big from a FAT16 point of view. What I do is mounting a network drive and mounting the image on the virtual drive from it. It works very well will all tested games even on 10 Mb/s NIC, even more considering the access is on a Windows 2000 VM 🤣. But as soon as audio tracks are involved, I got regular small freezes (from ~100 to ~300 ms, very perceptible) no matter what machine is used. So for such games, two choices, disabling CD Audio, or copying the ISO locally.

And considering Pi solutions. Personally I hate this option. First, its external, so not integrated (obviously). Second, the Pi have to be started long before for the host PC to detect it on POST. Third, a Pi 4 can emulate an old PC ; I means I understand to use a Pi for MT/CM-32 emulation but why using such a powerful hardware to do emulate ATAPI commands... As a hobbyist project, that's okay, as an everyday usable thing however...

I actually would enjoy a raspberri pi as external drive bay solution. It's better than nothing or something really expensive but from the sound of it, there's nothing quite good enough yet.

It is simple... Even with a Raspberry Pi, you can't get the speeds need by the IDE/SCSI bus and still have enough processing power to emulate audio (specially if you want digital audio emulation) or copy protection (specially DPM). So anything you can get will be using an FPGA, or at least a speedy CPLD, increasing the cost.
In resume, we will not find 15USD solutions if that's what we are waiting for.

Just a question out of curiosity:
How do these CD emulators handle copy protections like laserhole etc?

hyoenmadan wrote on 2021-09-15, 15:34:

It is simple... Even with a Raspberry Pi, you can't get the speeds need by the IDE/SCSI bus and still have enough processing power to emulate audio (specially if you want digital audio emulation) or copy protection (specially DPM). So anything you can get will be using an FPGA, or at least a speedy CPLD, increasing the cost.
In resume, we will not find 15USD solutions if that's what we are waiting for.

I completely agree. It is like wanting a Ferrari, but only willing to pay enough to buy a Yugo.

I looked up the 180Mhz Cortex, which is what is on the $200 unit and the cost of the chip by itself is probably around $14 not including shipping. I don't know the exact model of the chip being used on that unit so it may be even higher.

Then you have the other parts and the PCB and assembly, testing, etc. It adds up an it seems like almost nobody can fathom how it adds up.

hyoenmadan wrote on 2021-09-15, 15:34:

It is simple... Even with a Raspberry Pi, you can't get the speeds need by the IDE/SCSI bus and still have enough processing power to emulate audio (specially if you want digital audio emulation) or copy protection (specially DPM). So anything you can get will be using an FPGA, or at least a speedy CPLD, increasing the cost.
In resume, we will not find 15USD solutions if that's what we are waiting for.

Think the GPIO port is not fast enough, but the Cortex-A72 has absolutely the power to manage several ATA133 channel in parallel... Anyway, I maintain using a Pi to simulate an IDE drive is nonsense, why not using an iMac mini through a firewire 800 to IDE adapter. It's great hacking and I love such experiment, but cannot be a viable solution.

DPM... Good question. Is DPM requiring a lot of processing power? I don't think so. SecuROM 7 is a problem for burned media, RMPS is required. But through an ODE... At worse, protection sequences have to be detected, and in any case if data position is on the image, the firmware just have to map the data to the position. Audio is the same, I think it consist to read binary PCM data, adapting them to a DAC and voila audio output. Quite less complex than with a virtual drive. That's assumptions, I may be totally wrong but I doubt it.

retardware wrote on 2021-09-15, 15:59:

Just a question out of curiosity:
How do these CD emulators handle copy protections like laserhole etc?

I was asking the same question.
Protection data is embedded on the image, if they can read a CloneCD or DT image, as the protection is driven by software, if detected can be bypassed. I don't think there such code in any, so I think, protections will fail.
But that can be added in firmware as I said before.

hyoenmadan wrote on 2021-09-15, 15:34:

It is simple... Even with a Raspberry Pi, you can't get the speeds need by the IDE/SCSI bus and still have enough processing power to emulate audio (specially if you want digital audio emulation) or copy protection (specially DPM). So anything you can get will be using an FPGA, or at least a speedy CPLD, increasing the cost.
In resume, we will not find 15USD solutions if that's what we are waiting for.

I would be willing to get a Mister and an addon card for this, IF the addon card is reasonably priced. The problem is that the current solution is inadequate and can ONLY be used for this application. If we could use a Mister as a SCSI device (an external CD drive) it would let you use it for various other solutions as well. Heck, you can use a Mister as a Roland MT-32 as well I believe.

red_avatar wrote on 2021-09-17, 10:29:

I would be willing to get a Mister and an addon card for this, IF the addon card is reasonably priced. The problem is that the current solution is inadequate and can ONLY be used for this application. If we could use a Mister as a SCSI device (an external CD drive) it would let you use it for various other solutions as well. Heck, you can use a Mister as a Roland MT-32 as well I believe.

No, the MiSTer support MT32-Pi running on a Raspberry Pi 3 or 4. With the IO board and a Pi hat, it's possible to have the Pi be powered by the MiSTer over a USB cable and pass the audio back through that cable and be mixed internally.

If a Pi's GPIO can't handle the bandwidth requirements, the DE10-Nano the MiSTer runs on probably won't be able to either.

SScorpio wrote on 2021-09-17, 11:49:

red_avatar wrote on 2021-09-17, 10:29:

I would be willing to get a Mister and an addon card for this, IF the addon card is reasonably priced. The problem is that the current solution is inadequate and can ONLY be used for this application. If we could use a Mister as a SCSI device (an external CD drive) it would let you use it for various other solutions as well. Heck, you can use a Mister as a Roland MT-32 as well I believe.

No, the MiSTer support MT32-Pi running on a Raspberry Pi 3 or 4. With the IO board and a Pi hat, it's possible to have the Pi be powered by the MiSTer over a USB cable and pass the audio back through that cable and be mixed internally.

If a Pi's GPIO can't handle the bandwidth requirements, the DE10-Nano the MiSTer runs on probably won't be able to either.

Seems like a Rpi ZeroW 's secondary memory interface (SMI) can have a speed of 83MBytes/sec. Should be fast enough 😉

weedeewee wrote on 2021-09-17, 12:17:

Seems like a Rpi ZeroW 's secondary memory interface (SMI) can have a speed of 83MBytes/sec. Should be fast enough 😉

A 1x CD-ROM transfers 150KB/sec. Audio shouldn't matter as that can be output out over the Pi's analog audio output.

How much overhead does the IDE interface add?

SScorpio wrote on 2021-09-17, 18:02:

weedeewee wrote on 2021-09-17, 12:17:

Seems like a Rpi ZeroW 's secondary memory interface (SMI) can have a speed of 83MBytes/sec. Should be fast enough 😉

A 1x CD-ROM transfers 150KB/sec. Audio shouldn't matter as that can be output out over the Pi's analog audio output.

How much overhead does the IDE interface add?

I have no idea 😀

My guess is it is at least partially because of how the ATA protocol works. Plus you have interrupts, etc.

https://en.wikipedia.org/wiki/Parallel_ATA

What I still don't get is: if there's no cheap ways to get this to work, how come there are cheaper ways for consoles to have their CD drives replaced by SD card operated boards that DO support CD audio?

red_avatar wrote on 2021-09-17, 20:27:

What I still don't get is: if there's no cheap ways to get this to work, how come there are cheaper ways for consoles to have their CD drives replaced by SD card operated boards that DO support CD audio?

I've wondered about that myself... though... I've been stuck at wondering 😁

weedeewee wrote on 2021-09-17, 20:33:

red_avatar wrote on 2021-09-17, 20:27:

What I still don't get is: if there's no cheap ways to get this to work, how come there are cheaper ways for consoles to have their CD drives replaced by SD card operated boards that DO support CD audio?

I've wondered about that myself... though... I've been stuck at wondering 😁

Well the XStation costs €90 and that is basically what I want for PC: it supports CD audio AND can handle ISO, bin/cue, CCD/img (so more than that overpriced board linked earlier). Heck, the freaking board has onboard wifi letting you connect to it remotely!

red_avatar wrote on 2021-09-17, 20:45:

weedeewee wrote on 2021-09-17, 20:33:

red_avatar wrote on 2021-09-17, 20:27:

What I still don't get is: if there's no cheap ways to get this to work, how come there are cheaper ways for consoles to have their CD drives replaced by SD card operated boards that DO support CD audio?

I've wondered about that myself... though... I've been stuck at wondering 😁

Well the XStation costs €90 and that is basically what I want for PC: it supports CD audio AND can handle ISO, bin/cue, CCD/img (so more than that overpriced board linked earlier). Heck, the freaking board has onboard wifi letting you connect to it remotely!

thing with most of those is that the cdrom is more integrated in the device.

I would guess that modding an existing pc cdrom drive to use such a device as a replacement for the physical discs could be possible. Though, just guess 🙂

red_avatar wrote on 2021-09-17, 20:27:

What I still don't get is: if there's no cheap ways to get this to work, how come there are cheaper ways for consoles to have their CD drives replaced by SD card operated boards that DO support CD audio?

Not dealing with signal and software layers computers, and specially PCs have to deal (all for the sake of OS/device compatibility while retaining performance). Ofc if all you want is some form of PIO speed access and analog audio... Probably a speedier CPLD would still do it... Ofc you still will not get anything for 15USD. 90$ - 120$ would be the sweet spot range.

But as soon as you want some UDMA with Digital Audio + Copy Protect emulation (for games would need all of it at same time) and Windows support, you are done. Only an FPGA will do it, and then you will not find anything for lower than $150 bucks.

Alternatively people has skipped processing and direct emulation of the ATA protocol and signals by using second hand unused ATA interface ASICs (supposing you could also get access to the developer tools some of them need to get deployed (i.e. get the chip out from manufacturing mode))... Then you could pair that with some ARM CPU or CPLD to provide the data, copy protect and analog audio emulation... But I dunno how much that would lower the final price of the device.

PD. In effect. I've checked the XStation and it uses one of these new gen Intel Cyclone FPGAs + ARM cpu chips (while not having to deal with ATA packet processing, in realtime, at UDMA speeds btw). This at least confirms a CPLD will not do it. Now... These FPGAs aren't cheap... So most probably XStation developers have a sort of agreement with chip and electronic suppliers to get them on discount per volume (after all the XStation isn't the only thing they do).

Merged with the other thread and moved back to Marvin -> General Old Hardware.

red_avatar wrote on 2021-09-14, 10:24:

I'm rather puzzled really. The past few years we've seen projects that have found a way to emulate pretty much everything under the sun, new Sound Blaster compatible sound cards and a host of other things yet one of the few hardware elements that have actual physical wear a tear and are bound to die, namely the CD drives, are yet to have some solution? It's puzzling.

Seeing FPGA and how powerful it is, would there not be a way to incorporate a Mister as a CD drive, using a small display at the front where the tray would be to swap between CD images of all kinds (similar to the floppy GoTek drives)? Because honestly, besides the fact that having 30 CD wallets with all my games is a drag and they get damaged by use, it's becoming harder and harder to find a low speed CD drive that doesn't sound like a freaking JET ENGINE when it spins up. A half decent CD quad speed easily costs €60+ without shipping and you still have no clue how long the laser will still last.

It's especially odd considering consoles such as the Playstation already received projects that replace the CD drive yet the PC doesn't ... weird.

I guess you didn't know about the other thread listing some potential solutions? I merged your thread to it. Feel free to read from the beginning.

Bondi wrote on 2021-09-14, 12:33:

There is also MacSD http://macsd.com/index.php […]
Show full quote

There is also MacSD http://macsd.com/index.php

Compatibility:
Most SCSI-equipped Macintosh computers
SCSI Manager
SCSI Manager 4.3
Windows 98
Windows XP
MS-DOS 6.22
Adaptec 29xx-series SCSI cards

Wow, he's pretty nearby to me! Wonder if I know him IRL...

cyclone3d wrote on 2021-09-14, 13:18:

This topic comes up quite often. Here is an IDE emulator with audio support:
https://shop.tattiebogle.net/product/prod_EkTnv3Tk2Trxhf

The creator of this has a VOGONS account ("electric_monk") and takes support requests! Now that I've merged the threads together, you can read what he has to say on its development earlier in the thread!