Coming soon! Steem SSE 3.8

[Steven Seagal]

He he you've been waiting for this, right?

Developments screens are here:

http://ataristeven.exxoshost.co.uk/Stee ... _soon1.htm (ACSI)
http://ataristeven.exxoshost.co.uk/Stee ... _soon2.htm (refactoring)
http://ataristeven.exxoshost.co.uk/Stee ... _soon3.htm (features)
http://ataristeven.exxoshost.co.uk/Stee ... _soon4.htm (fixes)

Here is a nice schema presenting features:

SteemBeta380c-min.png

You may remark the wrench icon for configuration files, and some icons in the status bar instead of some previous text.
For example, "ADAT" is now the charming snail, it's easier to understand.
Chipset 1 is IKBD, ACIA, MIDI, e-clock, chipset 2 is still only the MFP.
For 'Hacks', it's the same icon as for patches. It seems appropriate, please tell me if that's confusing.

(edit fix typos)

[Steven Seagal]

ACSI is the Atari version of SCSI.
You may be a pro now, using one of those shoeboxes:

sh204.jpg

There will be at least a SH204.img file included in the download (preformatted, don't worry).
The file name will be the unit name for the driver:

acsi_ahdi_boot3units.png

Steem handles up to 4 units, of course.

The new icon:

acsi_icon2.png

Right click to toggle on/off, and the nice little hard disk icon appears in the status bar or disappears.

(edit fix typos)

[Steven Seagal]

I seriously reviewed blitter emulation, and tested all sorts of cases.
There were some bugs in v3.7.2 and older, unfortunately, now I'm unaware of any remaining non-working case,
but some will certainly show up after release day, as usual.
Note that I could compare with a real STE, and when there's bad display in Steem, there's bad display on the STE.
(EDIT: and in some cases, it displays fine in Steem but not on the STE: what should we do?)
Suspicion: it could be different on a Mega STE, and sometimes the version of TOS is important.

The pinnacle of blitter emulation is this:

blitbench.png

[Steven Seagal]

So configuration files are a new option beside memory snapshots.
This includes all your current options (including joystick and shortcut sets - which are separate files, a request).
In fact it's a copy of steem.ini at this moment. It's radical, but it also minimises code footprint.
You may have a configuration for programming, for STF, for STE, specific for some games.
Loading a configuration file resets the ST.
Carefully edited, those ini files could also be publicly used to help people run programs (I made the precise TOS path unnecessary).

[Steven Seagal]

Those are the most visible features. The rest is mostly "internal", I spent the time necessary to "refactor" (review and rewrite) some crucial aspects of video timings and "shifter tricks", now mostly "GLU (or GLUE) tricks", but this doesn't really change the outcome. Fewer hacks in the code, same cases are supported. Some nasty, sometimes ridculous bugs were removed as well.
Program compatibility will be very high in Steem SSE v3.8.

Coming soon!

[dlfrsilver]

That's awesome Thanks for your efforts Steven !

[bj]

Looking very good indeed. Can't wait to try out ASCI emulation and see if I can get Magic multitasking OS up & running reliably. Many Thanks for keeping on keepin on!

[thephantom]

Fantastic stuff once again, Steven – can't wait for this!

[Steven Seagal]

In v3.7, there was already an option for PAL aspect ratio, but it worked only in D3D fullscreen mode, pal.
Now it will be available for window mode too (low res and medium res) if you choose "double stretch" in the display options.
For the pics attached, the ratio is 10% (on http://ataristeven.exxoshost.co.uk/Stee ... _soon3.htm I think it was 15%).
Also included is a snaphsot I took myself from real STE + CRT.

edit: insert stupid pun

[dlfrsilver]

That's another cool feature, which was indeed missing

[Steven Seagal]

I should have added it together with D3D fullscreen but I thought it was complicated.
In fact it's very simple, like 2 lines of code.

This is no fancy option. Of course, picture height could be - somewhat - corrected on most good monitors (not TVs), but many graphic artists used the typical ST aspect ratio when creating their art.
With this option, you may see the screen as the artist, and the player, did. This is the real Atari ST experience.
Also notice that the left border isn't cut off: Steem's big display rendering was right (like my high-flying theories).

I think there's a technical explanation for this A.R.

[Mikefulton]

There's a fix I'd like to see to the extended monitor hack.

Currently, it's setup to do its thing only on the first open workstation call. It fails if a version of GDOS is loaded.

It should be checking the device ID to make sure the request is for the screen, and it should do the line-a patching every time, not just the first time. The only first-time-only bit should be allocating memory for the screen buffer.

Also, allocating memory for the screen buffer should not be done with Malloc as this will put it at an arbitrary location.

I recommend that allocating the screen buffer should be a separate thing from patching line-a. Put it at the end of RAM and set the _memtop system variable to keep the buffer out of the TPA.

[catmando]

Great, very good

[Steven Seagal]

There's a fix I'd like to see to the extended monitor hack.

Currently, it's setup to do its thing only on the first open workstation call. It fails if a version of GDOS is loaded.

It should be checking the device ID to make sure the request is for the screen, and it should do the line-a patching every time, not just the first time. The only first-time-only bit should be allocating memory for the screen buffer.

Also, allocating memory for the screen buffer should not be done with Malloc as this will put it at an arbitrary location.

I recommend that allocating the screen buffer should be a separate thing from patching line-a. Put it at the end of RAM and set the _memtop system variable to keep the buffer out of the TPA.

I take no more requests for v3.8.0 but I'll check it later. Sounds intricate.
Notice this thread for requests: http://www.atari-forum.com/viewtopic.php?f=94&t=26998

[By the way, I know those twin "Coming soon" threads are kind of confusing.
If I start one for v3.9 please stop it.]

[Steven Seagal]

This thread needs a little bump (almost wrote dump).

Remark the option for ST aspect ratio has been moved, because it works with both D3D fullscreen and window-stretch-double.
It's also renamed PAL which is even cooler.

options_sse_380.png

Just above, you can see that options VSync and Triple buffering can be checked, even though the system is Windows 10.
At your risk. On my system VSync works with windows and fullscreen, but triple buffering slows things down.

options_display_380.png

Here you can see how display options have been rearranged.
'Borders' is now on or off, forget the auto mode.
The 'Display size' option on the right is disabled if 'Borders' are off, which is kind of logical.
The displayed choice, 384 x 270, is Steem's original size. It is what you would get on most LCD screens, and maybe on TVs or some other monitors. This recently has been discussed in the context of new demos.
With larger sizes, you get what a good CRT monitor would display ("fullscreen", "plasma"...).
Well, the right border still isn't perfect, but emulating the strange cut off effect of "HBLANK" isn't easy.

[Steven Seagal]

Some theorics


You need "round cycles up to 4" only for RAM and Shifter accesses.
Funny but this was already in the Engineering Hardware Specification of 1986:

Code: Select all

            ---------------
          | MC68000 MPU   |<--
          |               |   |
           ---------------    |
                              |                           ----------
                              |<------------------------>|192 Kbyte |<--->EXPAN
                     ---------|------------------------->| ROM      |
                    |         |                           ----------
                    |         |                           ----------
                    |         |                          |512K or 1M|
                    |         |                       -->| byte RAM |<--
            ----------        |        ----------    |    ----------    |
           | Control  |<----->|<----->| Memory   |<--                   |
           | Logic    |-------|------>|Controller|<--                   |
            ----------        |        ----------    |    ----------    |
             |||||            |        ----------     -->| Video    |<--  RF MOD
             |||||            |<----->| Buffers  |<----->| Shifter  |---->RGB
             |||||            |       |          |        ----------      MONO
             |||||            |        ----------
             |||||            |        ----------         ----------
             |||||            |<----->| MC6850   |<----->| Keyboard |<--->IKBD
             |||| ------------|------>| ACIA     |       | Port     |
             ||||             |        ----------         ----------
             ||||             |        ----------         ----------
             ||||             |<----->| MC6850   |<----->| MIDI     |---->OUT/THRU
             ||| -------------|------>| ACIA     |       | Ports    |<----IN
             |||              |        ----------         ----------
             |||              |        ----------         ----------
             |||              |<----->| MK68901  |<----->| RS232    |<--->MODEM
             || --------------|------>| MFP      |<--    | Port     |
             ||               |        ----------    |    ----------
             ||               |                      |    ----------
             ||               |                       ---| Parallel |<--->PRINTER
             ||               |                       -->| Port     |
             ||               |        ----------    |    ----------
             ||               |<----->| YM-2149  |<--     ----------
             | ---------------|------>| PSG      |------>| Sound    |---->AUDIO
             |                |       |          |---    | Channels |
             |                |        ----------    |    ----------
             |                |                      |    ----------
             |                |        ----------     -->| Floppy   |<--->FLOPPY
             |                |<------| WD1772   |<----->|Disk Port |     DRIVE
             |                |    -->| FDC      |        ----------
             |                |   |    ----------
             |                |   |    ----------         ----------
             |                |    -->| DMA      |<----->|Hard Disk |<--->HARD
             |                |<----->|Controller|       | Port     |     DRIVE
              ----------------------->|          |        ----------
                                       ----------
 

See how the Memory controller (MMU) sits between the CPU and the RAM/Shifter?
I bring this up because it's a very old schema, and it explains nicely this "rounding" mess.
Steem didn't work like that. It would round up for all bus accesses, except some instructions, like MOVE, didn't at all!
So writes to GLUE (resolution, frequency) weren't rounded, Steem had this 2-cycle precision for "Shifter tricks" and I wondered why...
This hack has been finally removed in v3.8.
Notice that R/W to the Shifter itself should be rounded, so it's essential to know where registers are.
R/W to other peripherals shouldn't be rounded, but there are wait states anyway.
In the schema above, there's also "Buffers" near the Shifter, don't know what it is.

[Cyprian]

cool

'Borders' is now on or off, forget the auto mode.

I use color for demos watching and borders visibility is 'a must' but also very often I use mono mode and there borders are really useless. Therefore would be nice to have another option for 'Borders': "Color On / Mono Off"

[Steven Seagal]

As I bragged in another thread, Steem SSE 3.8 will (more or less) support a cool monochrome demo:

time_slice.gif

It uses the STE's hardware horizontal scrolling in high res, which was already emulated, and "monochrome raster effects", if this makes sense.
I added support for that, but with a byte resolution only, because it's coded in C++, not in assembly like for colour rasters (Steem authors coded the assembly, I can't).
It seems faithful for the "ST NICCC 2015" effect.
The greeting scrollers don't look good.

PS: don't try to watch the demo with previous Steem versions

edit: here with the scrollers

time_slice2.gif

[Steven Seagal]

cool

'Borders' is now on or off, forget the auto mode.

I use color for demos watching and borders visibility is 'a must' but also very often I use mono mode and there borders are really useless. Therefore would be nice to have another option for 'Borders': "Color On / Mono Off"

Borders are a must for another monochrome demo Steem SSE supports more or less:



The scroller is in overscan!

[Cyprian]

Borders are a must for another monochrome demo Steem SSE supports more or less

true, therefore I asked about adding (not replacing) a new option

[troed]

Notice that R/W to the Shifter itself should be rounded, so it's essential to know where registers are.

Where "is" $ffff8260?

/Troed

[Cyprian]

in the Shifter and also in the GLUE? and rounded to 2cycles in case of the GLUE?

[troed]

in the Shifter and also in the GLUE? and rounded to 2cycles in case of the GLUE?

Yes Both GLUE and Shifter observe it and the GLUE can definitely detect manipulation of it with 2 cycle accuracy. I don't know if it's rounded to four for the Shifter but maybe it is.

Hmm, actually it's possible to test (visibly) so maybe I should do that.

/Troed

[Steven Seagal]

For the moment, to determine timing/rounding, Steem 3.8 considers that only palette registers are in the Shifter.
But obviously, shift mode and HSCROLL are in the Shifter, with maybe only a bit for each in the GLUE (on/off).
Possibly, GLUE sets/clears its bit 2 cycles before the Shifter gets all bits (2 for mode, 4 for HSCROLL) in some cases.
Sync mode, LINEWID would be in the GLUE.
And video counter registers (VBASE...) in the MMU.

EDIT: In fact LINEWID should be in the MMU, which would do the operation A+Bx2=C

[elluigi]

Hi Steven,

Many thanks for your program and great support on it

This is probably not the place but I would like to ask you if it will be possible to add a shortcut which allow to swap ST Model (very useful with DBST and many other games/progs ). New features ?