Preparing for AmiWest 2013

blog_devAmigaOS fans may have noticed an abundance of updates appearing lately. There is also an updated SDK should be appearing soon as well.

One of the reasons for all this activity is AmiWest 2013. The show itself is October 19 and 20. There is also a “Classic Clinic” on the Friday night before the show where Amiga technicians will be available to help get your Amigas up and running again. AmiWest is also featuring a programming conference from October 16 to 18. The plan is to continue where we left off at AmiWest 2012 and focus on building useful applications with a GUI. It is the programming conference which is driving the bulk of the updates. We want everyone to be at the same API level and have all the latest updates so we don’t waste any time on working around any fixed bugs (for example).

Many AmigaOS core developers and beta testers will be attending AmiWest 2013. This is your chance to chat face to face with the experts that are building and maintaining the genuine Amiga Operating System. Hyperion Entertainment is also sponsoring the show and will have a table setup with various AmigaOS-based systems on display. See you there!

Steven Solie
AmigaOS Development Team Lead

HDAudio driver is complete!

blog_devI am happy to announce the release of the finished HDAudio driver for the AmigaOne X1000!

The driver now supports recording as well as playback. It also now supports S/PDIF optical output.

There have been questions about whether full “32 bit” audio really makes a difference. I’d like to dig a little deeper to better understand the technical specifications.

There are two primary factors that contribute to the quality of a digital sound recording. One is resolution, or how many bits per sample, and the other is sample rate, commonly 44100 or 48000 samples per second.

As you look at the waveform of a sound recording, these two numbers determine the vertical and horizontal resolution of the wave.

I’ll begin with the “bit width” or vertical resolution.

The original Amiga’s sound output supported four channels at eight bits of resolution. Eight bits means there are two hundred and fifty six possible vertical “steps” that can be used as the wave is generated. Now we spread those steps across a -2 volt to +2 volt span and we get 0.015625 volts per step.

At the time of the Amigas introduction, that was a pretty fair sound playback. But only 256 steps is not as “high fidelity” as we might like. As a comparison, Compact Disk Audio is reproduced at 16 bits per sample. This makes for a big improvement in resolution. 16 bits offers us 65536 possible “steps” to spread across the -2 volt to +2 volt range. Now the step size is 0.0000610351562 volts per “step” of vertical resolution. So 16 bit audio is a HUGE increase in accuracy.

Getting back to our driver, AHIPrefs offers both 16 Bit HiFi and 32 bit HiFi modes. But I’ll bet that neither of those modes gives exactly what you might expect. As AHI mixes lots of different sounds together, possibly each sound with it’s own volume and pan settings, it can be useful to have more resolution available to work with. Here’s the clue: ALL AHI modes that say “HiFi” are sending 32 bit data out to the sound device! The “16” and “32” only describe what goes IN to the AHI mix routines. if it says HiFi, you WILL get 32 bit output to your card!

Or will you? In truth, while AHI is making it’s calculations using 32 bit registers and 32 bit math, it only promises 24 bits of accuracy. Is this anything to be concerned about? Not at all. I’ll tell you why. 24 bit samples will resolve to a “step size” of 0.0000002384185 volts per step. Wow! That is about one quarter of a microvolt. Those with an electronics background can probably tell you, that attempts to accurately work at those levels are just ridiculous. We have reached an accuracy that is beyond the ability of our amplifiers and speakers to reproduce. Put simply, 24 bits is the reasonable limit of current technology, or at least affordable technology.

So our 32 bit samples are flying out of AHI and in to the HDAudio codec. While the “container” is 32 bits wide, even the “high definition audio codec” that we have in the AmigaOne X1000 only resolves the top 24 bits. So it seems that in the end, both AHI and HDaudio agree that 24 bits is the reasonable limit for now.

And how about sample rate or the “horizontal” resolution?

How rapidly a sound is sampled and played back can also have a BIG impact on sound quality. It all starts with the Nyquist-Shannon sampling theorem or more commonly the Nyquist theorem. It’s pretty simple. As you record an audio signal, you must sample at at least twice the frequency of the highest pitch being recorded. Any sound that is higher than half the sampling frequency will be converted to noise and nasty noise at that.

So how high do we need? It is generally held that human hearing range is from 20 Hz (cycles per second) up to 20000 Hz. So any frequency above 40000 should be great right? Well Yes and No.

One simple problem is that we still must filter out all sound above half the sample frequency, and most frequency dependent volume controls (graphic equalizers) work with gradual slopes. There is no “hard cutoff” at a certain frequency, so we need a bit of headroom.

But there is another reason. As a high frequency sound approaches the Nyquist rate, we are only sampling about once per half-cycle. While this will reproduce the frequency of the original, it will do it at a bare minimum of accuracy. In other words, as frequencies get higher, they get less detail.

So what does it really matter?
Audio CDs play back at 44100 Hz. Not bad at all.
Television/DVD audio is usually at 48000 Hz. Nice.
With the HDAudio chip in the X1000 we support both of those frequencies.
We also support 88200, 96000, 176400, and 192000.
So we can double or quadruple the sample rates of common media!

At first, I really thought it was all a numbers game, but when developing the driver, I can actually hear the noise decrease noticeably as the playback rates went up!

And that is where I’ll leave off. This was enough of a lesson for one day. I am very happy that I could contribute to the completion of this driver. And the chance to “raise the bar” regarding sound capability was really very nice icing on the cake.

Like many of us, I have been using Amigas for a long time. Today, right here in front of me is an Amiga that supports high definition audio, a modern high performance video card. It uses standard, off the shelf keyboard, mouse, monitor and many USB accessories as well. Most of these we unheard of in the classic days. But with all the new and shiny, it is still AmigaOS to the core.
:)

New AmigaOS Core Developers

blog_devWe are pleased to announce that we have joined the AmigaOS development team. We hope that we are able to contribute some good things to AmigaOS using our skills in coding (Frank) and graphics (Thomas).

The follow is a short description of us and our products.

EntwicklerX:
We are currently working full time, self-employed, developing our games on multiple platforms (AmigaOS, Android, iOS, Windows Phone, Xbox Indies) as EntwicklerX. For about 10 years we have worked together on various software projects in our spare time. The focus in the last 5-6 years was to earn some money with the small bonus that it has allowed both of us to live from it (not enough for a Ferrari but enough to have fun at work). A strict separation between design and programming logic helped us build our products in an effective way with our limited time. While Frank takes care of programming, Thomas builds the graphics. Our subsystem is so sophisticated that Thomas can create and test Layouts without the help of Frank and Frank can use this directly in his code. This saves a lot of time and nerves. Before this, Frank had to compile every time if Thomas wanted to move a graphic a few pixels. 😉

AmiBoing Games

Our Amiga platform AmiBoing is used to bring an online connection to our games for high scores and achievements and it is also used for distributing our games. With more than 200 Users we can say this is the leading online gaming community on the Amiga platform. 😉

avatarImago_small

Thomas:
I care about what the user sees, how users interact with a game, paint graphics, create the levels and take care of our website. I have invested a lot of time into understanding how to create themes for AmigaOS and am still learning. The seamless design of an operating system is very important to me and I hope to play a part in this within AmigaOS.

avatarGoos_small

Frank:
I try to bring Thomas’ graphics to life and love to get the maximum out of AmigaOS using any available techniques to optimize (e.g. compositing). In our projects, I take care of all the programming. Together with Thomas, I am working on the game play and new game ideas. I can do my part in helping the Amiga in all areas of coding and to help current developers.

We are a Team:
Even with the split of responsibilities we will usually work as a team because ideas and their implementation always occur together. We look forward to working with the existing developers and also contributing to any interesting discussions. We will do our best but please note that we are only human and have a finite amount of time to work on everything. Give us time to understand how things work within the developer team. 😉

Best regards and let us say thank you for adding us to the list of AmigaOS core developers,
Thomas “imagodespira” Claus and Frank “Goos McGuile” Menzel.

Some Links:
EntwicklerX: www.entwickler-x.de
AmiBoing: www.amiboing.de
Themes: www.amiboing.de/themes.php

M.A.C.E

ThemeScreenshot

Delock PCI Express Sound Card supported

blog_miscAndreas Goiczyk has reported that the Delock PCI Express Sound Card 7.1 works well with the newly updated Envy24HT audio driver.

Thank you Andreas for letting us know!

If you discover a sound card not listed is supported by an AmigaOS audio driver, please use the contact form on the AmigaOS web site to let us know.

More Noise from ACube

blog_softwareThe VIA Envy24HT audio driver has been updated and now supports the VT1618 Codec. That means you can now use inexpensive PCIe audio cards such as the Syba SD-PEX63034 in your AmigaOne 500 and AmigaOne X1000 systems.

Here is a list of audio cards that are known to work with the Envy24HT audio driver:

  • Terratec Aureon 5.1 Sky
  • Terratec Aureon 7.1 Space
  • Terratec Phase22
  • Terratec Phase28
  • M-Audio Revolution 5.1
  • M-Audio Revolution 7.1
  • ESI Juli@
  • ESI Juli@ XTe
  • Speed Dragon EAU01A-1
  • Syba SD-PEX63034

If you happen to have audio card not on this list which also works with this driver please notify us via the AmigaOS contact form.

Special thanks to ACube Systems for helping to improve the Envy24HT driver.

The updated driver is being delivered to registered AmigaOS users using AmiUpdate. If you have any support issues with the driver please use the AmigaOS support forum for assistance.

Confessions of an Audioholic

blog_devThe HDAudio driver has recently been released to AmigaOne X1000 owners. This driver supports the built in “high definition audio” chip used in this computer.

I am the last coder to work on this driver, but like a relay race, much of the hard work was done before it was passed to me. Davy Wentzler, Alex Carmona, and René W. Olsen did a lot of the heavy lifting before I started on the project.

As far as I know, this is the first AmigaOS 4 driver to support the High Definition Audio standard. this is a new specification from Intel, destined to replace the older AC97 standard. This new standard includes lots of improved specifications in audio fidelity.

We can now play sound out the back and the front headphone at the same time. This has led to having “All” as an option when choosing an output.

It is possible to signal the software when a plug is inserted or removed. And it’s even possible to do a quick “impedance check” when a device is plugged in, and then make a good guess about whether it is a microphone (low level), stereo feed (line level) or the output from an MP3 player (higher level).

The HDAudio standard offers us a lot of new features that we will be exploring for a while to come.

The process of “bringing up” this driver included a few good challenges.

AHI reads a “modefile” that describes the basic features of the sound driver. It opens the driver and asks it to go looking for a matching sound card. If one is found, the driver / card is added to the system.. but when sound gets played it gets more interesting..

AHI specifies to the driver how many channels, how many bits per sample, and how rapidly the samples are about to start coming in. The driver needs to set up the sound chip for this, but it really NEVER talks directly to that chip! Instead it sets up the SB600 (Southbridge) with details about buffer sizes and all the other info that AHI just provided. It also builds up a “command buffer” for talking to the sound chip, and a “response buffer” that lets the chip answer. So we now have the southbridge set up to carry sound for us, and to also handle all our control communications with the sound chip as well.. Easy, right?

Imagine how overwhelmed I was on the first day of reading all this code!

704px-amiga_1000dp

Amiga 1000

Fortunately the ground work was well done already. I started by just testing the ability to send commands and get responses. Looking over the documents, I see a command to tell the chip to “beep” all by itself, without any audio data. That was the first success! Not too fancy, but it’s proof that we can talk to the sound chip. Alex Carmona picked up that code, and used it to make a “boot sound” for X1000 owners that sounds a LOT like the original Amiga 1000.

Next up, I separated the AHI part from the SB600/sound chip part. My thinking was that it’s easier to divide and conquer. Then I worked hard on opening the audio path to the sound chip. Before too long, I had noise, but it never sounded quite right. It turned out that the buffers feeding in to the sound chip had to be handled a bit differently. I’ll try to explain:

The normal way to feed a constant stream is called double-buffering. The idea is simple. While the audio chips are playing buffer A, I’ll be filling the next sounds into buffer B. Once the player moves into buffer B, I’ll fill more into A, and keep on going. Simple, right?

Of course it is never as easy as it sounds.. A bit of digging and I learned that instead of two separate buffers, the SB600 really wants one continuous block of memory! Simple enough, I’ll just get one big block, and draw an imaginary line halfway through it.

Now to keep things simple, I start by asking AHI what size it’s buffers will be, then I make the SB600 buffers the same size. Really one big buffer the size of BOTH AHI buffers combined.. but the sound wasn’t right yet. Keep digging.. AHI gets the buffer size it wants, the SB600 gets one big buffer, which looks to AHI like two buffers side-by-side.

Now it turns out that the sound chip has buffer size limits too, and they are a LOT smaller than any of the previous buffer sizes!

The final result is one big memory block for the SB600, split into two buffers, each sized to match what AHI wants, with each of those buffers split into as many smaller “segments” at or below the max size that can be handled by the sound chip. Wow. One block of memory divided up three different ways, depending on which way you look at it.

kiss-band

Not the KISS principle

I’ll mention here that I was looking for ANY way to make it simpler.. and all of this “memory geometry” would change with every change in sound settings! So the K.I.S.S. principle took over. I decided to configure everything AFTER AHI to ALWAYS run in 8 channel 32 bit quality. Running that way, I can easily “upsample” ANY sound format coming out of AHI to one stable format. If AHI sends me mono, I copy it to left and right, and zero the other six. If it sends stereo, the last six stay muted too. If it sends me 16 bit audio, I just shift it to the high word of the 32 bit samples.

Once all that buffer stuff was wrestled into submission, we finally got good sound coming out!! Success!!!

The modefile that came with the driver had only ONE mode. Not really a good way to show off such powerful audio chips. But the previous modefiles were created with tools that we don’t have, and I could find NO documentation.. So I got to spend a day or two studying the modefiles. Once I got a good idea of how they worked, I wrote a program called “makemode” that converts a text file to a working modefile. If you need a tool, write it! This expanded our driver capability to as many modes as I choose to support (currently 3, including 7.1 audio). And as a side benefit, new modefiles can be created as quickly as they can be described. The sample rates have been increased as well. This chipset and driver support up to 192kHz, that’s about four times higher than the old “normal”.

The Beta test team has been a HUGE help in finding the little bugs that I missed. These last few versions have been pretty well behaved. If you are reading this then a public release must be “real soon”. We still have more to do, S/PDIF optical output and sound recording are still on the “to do” list. But the sound is playing, and that’s not a bad place to be today.

It has been a big team effort. Davy, Alex, René, the Beta team, and Steven for taking ENDLESS emails when I ran out of hair to pull out.

If you really read all the way to here, you get a special bonus tip: When you open SYS:Prefs/AHI to adjust the driver settings, you might try dragging the prefs window a LOT wider. The rear-panel connections for line out, line in, and microphone in are all described with the color of the correct connector listed. With six color coded jacks on the back, this might be helpful to get it into the right hole in one try. :)

Now that X1000 owners have an open PCI slot, what will be the most popular new “toy” to play with ?

Happy Easter

Brussels, March 31, 2013

Easter seems like an appropriate time to provide a short update on the development status of a few key components of the upcoming AmigaOS 4.2.

  • Exec SG  : kernel development has been forked off into an experimental and stable branch, to facilitate field testing of potentially drastically new features such as the scheduler, separate address spaces, 64 bit address space awareness etc.
    The task scheduler was completely rewritten in C and now implements the long planned “pluggable” scheduler functionality  : the scheduling algorithm can be changed on the fly, during runtime depending on factors like task’s preference and CPU load, different CPU cores using different scheduling algorithms. The re-write of the scheduler also allows for load balancing which is required for proper multicore support.
  • Work is in progress on yet another Power ISA implementation.
  • Gallium  : bumped to Mesa 9.1, i.e. OpenGL 3.1. Software renderer already implemented, work on hardware accelerated drivers within the framework of Gallium will benefit substantially by the experience gained developing Warp3D drivers for the AMD Radeon Evergreen range (Radeon HD 5xxx/6xxx).

Please note that whilst work on AmigaOS 4.2 is in progress, work on other components is also ongoing and will be made available via AmiUpdate to registered users of AmigaOS 4.1.

Hyperion Entertainment’s management and the AmigaOS 4.x development team wish to thank all of you who have provided much needed support of our efforts by buying AmigaOS 4.1 (either as a standalone copy or together with suitable Power(PC) based hardware available from our hardware partners A-EON Technology and A-Cube Systems.

We greatly appreciate your support and wish you a Happy Easter  !

Classic Cinemaware Returns to AmigaOS

As stated in the official press release, Cinemaware’s original 68K games have been re-released for AmigaOS.

Wings

Screenshot of Wings™ on the AmigaOne X1000

Using original Amiga ROMs and Workbench files along with the UAE emulator, current AmigaOS 4.1 owners can enjoy complete Amiga 68K emulation on their PowerPC based systems. The RunInUAE package by Chris Handley makes it possible to double click on each game to automatically launch UAE. There is even a JIT compiler in the works which should dramatically speed up emulation when it is completed.

dotc-a500

Defender of The Crown® on the AmigaOne 500

Each Cinemaware game utilizes WHDLoad to enable it to run with a simple double click of the mouse. WHDLoad may be registered to remove the nag requester and help support even more original Amiga game conversions.

All that said, the emulation is not 100% perfect. This is where you come in. UAE is very configurable and specific config files are provided for some games. If you know of any tricks to help improve those UAE config files please share them. There is also the decision to use WHDLoad versions of the games. Some people prefer ADF versions instead. Please consider helping us improve the games and possibly provide ADF versions as well. The best way to get in contact with us is via the contact form or the support forum.

rr-a500

Rocket Ranger™ on the AmigaOne 500

AmigaOS 4.1 Update 6 users should note they must have the Emulation and RunInUAE updates applied to their systems for smooth operation. If you have not yet updated, this is a great reason to do so.

I would like to thank the AmigaOS beta testing team for helping to find and fix the many issues that cropped up during beta testing. A special thanks must also go out to Lars Fuhrken-Batista of Cinemaware and Ben Hermans of Hyperion Entertainment for making this project possible.

Steven Solie
AmigaOS Development Team Lead

Are you AmiUpdated?

blog_updateSince the release of AmigaOS 4.1 Update 6 there have been over 25 updates released via the integrated AmiUpdate system.

AmigaOS customers can expect many more updates as we catch up on component releases. There may even be some new features slipped in now and then to keep things interesting.

Simply select “Update software…” from the Workbench menu and apply the updates when it is convenient to do so.

If you have any troubles with the new software update system remember that support is available at support.amigaos.net and we’ll do our best to help.

AmigaOS 4.1 Update 6 Released

AmigaOS 4.1 Update 6 has now been released.

More details and a place for registered users to download the update can be found at Hyperion’s main web site.

The following AmigaOS platforms are supported:

Update 6 is a rather unique update in that it includes no bug fixes. What Update 6 does include is a new and more efficient way of delivering bug fixes. A new “Update software…” menu item on Workbench now launches AmiUpdate which will now handle all future AmigaOS software updates.

Since AmiUpdate does not do much without a back end database, a new AmigaOS update database has been created. This database tracks dependencies between components so that users can be assured they are applying the correct updates to their specific systems. The rollback facility may be used to undo updates in the event of problems.

Users are strongly encouraged to install Update 6 as it will be the only way to receive future AmigaOS updates between major releases.

Special thanks to Simon Archer for his amazing AmiUpdate product and the AmigaOS testing team for their invaluable effort on this release.