Feature Requests

[exxos]

Hi
For requests, I changed my mind, it's better to open a new thread in the development sub-section of Steem in this forum. Easier to follow.
In Steem, there's the 14 MB hack.
I looked for "alt-ram", it seems part of something bigger (MonSTer?)

I think I've seen 14MB in there, but assume it operates as ST_RAM so alt-ram allocation wouldn't work with it. Monster has alt-ram. I plan to add alt-ram into my designs in the future also. It was a thought as it needs drivers to work, which need testing, also I need to test alt-ram benchmarks for gembench. Would just be easier to develop under steem than real hardware. Though its not a big issue, might be useful for some other uses not really sure.

[Steven Seagal]

Are there apps depending on alt-ram?
In that case that could be interesting for more people.
Also need specs and test programs...

[exxos]

Are there apps depending on alt-ram?
In that case that could be interesting for more people.
Also need specs and test programs...

I don't think there are apps which depend on it, Any app should be able to run in alt-ram though. Generally in the case of monster, it gives 8MB of alt-ram and just needs mxalloc to declare the RAM to the system. Then theres a program PRGFLAGs where it just lets you select the PRG flags to run in alt-ram.

Alan's alt-ram driver is here http://www.fairlite.co.uk/AtariKit/monster/monster.html

Can't just find the PRGFLAGS program, maybe someone here has it to hand ? Though I think if the monster driver finds the ram then all should be good anyway.

Likely as you give 14MB ST-RAM, it would have to be limited to 4MB max as alt-ram uses 8MB chunk..

In actual Fact GB6 benchmarks alt-ram if found.. So only really need alan's "driver" to declare the RAM as alt-ram and not ST-RAM and really should be good to go.

[Cyprian]

Can't just find the PRGFLAGS program, maybe someone here has it to hand ?

there you can find zip file with PRGFLAGs http://www.page6.org/st_lib/standard/st0672.php

[czietz]

I think it would suffice if you made the RAM above 0x400000 available (like in the 14 MB mode) but didn't patch the system variables so that TOS still only detects 4 MB of ST-RAM. Then, a very simple driver program could register that unclaimed memory (from 0x400000 - 0xDFFFFF) as Alt-RAM. Obviously that mostly benefits developers that for example want to test Alt-RAM handling of their programs. The "normal" user can always select 14 MB ST-RAM if he needs the extra memory.

PS: I have just verified that it can be done this way.

[czietz]

You don't even have to make changes to Steem SSE. Take the existing version, set it to 14 MB RAM and load the attached cartridge that I just coded. It'll split the available RAM into 4 MB ST-RAM and 10 MB Alt-RAM. TOS 2.06 required, obviously. Also: No error checking, so it'll crash hard when Steem is not set to 14 MB.

[Steven Seagal]

Hi,
I finally looked at it.
Steem doesn't hack system variables for the 14MB hack, it just hacks the MMU's 4MB limitation.
It makes sense because TOS tests for more than 4MB using R/W/bus error, which I didn't know before yesterday.

I added Monster's alt-ram support in an experimental build:

monstera2.png

The alt-RAM starts at $40000 and is activated by the driver by using IO addresses $fffe00 (#MB) and $fffe08 (firmware version), so the TOS won't see it at boot (I guess).
I don't know if the dude responsible for this hangs around here, but I don't get why $fffe00 can be accessed in CPU user mode (supervisor not needed), it complicates emulation!

monsterb2.png

It seems to work because to get to this screen, TOS 2.06's maddalt() was called and some allocation above 4MB has been done.

EDIT: dev build available

[exxos]

Hi,
I finally looked at it.
Steem doesn't hack system variables for the 14MB hack, it just hacks the MMU's 4MB limitation.
It makes sense because TOS tests for more than 4MB using R/W/bus error, which I didn't know before yesterday.

So TOS *is* capable of seeing more than 4MB ST-RAM then ? As in "all TOS versions" ?

[czietz]

So TOS *is* capable of seeing more than 4MB ST-RAM then ?

On a real (i.e. non-emulated) ST even though TOS supports more than 4 MB of (ST-)RAM, you will still need a custom MMU, because TOS will try to use this RAM of things like video (Shifter) memory and DMA. And that won't work with the builtin MMU.

[exxos]

So TOS *is* capable of seeing more than 4MB ST-RAM then ?

On a real (i.e. non-emulated) ST even though TOS supports more than 4 MB of (ST-)RAM, you will still need a custom MMU, because TOS will try to use this RAM of things like video (Shifter) memory and DMA. And that won't work with the builtin MMU.

Yeah, I know a "new" MMU would be needed. I remember some talks about this as a TOS limit some years ago. Obviously the Falcon supports 14MB ST-RAM, but what about other TOS versions...

[czietz]

I only know the algorithm for TOS 1.04. There it's like Steven said: TOS goes through the memory in 128k steps until either a bus error occurs or the test pattern previously written to that memory can't be read back. So any contiguous area of memory will be accepted as RAM.

[Marakatti]

Could there be a seperate volumeslider for STe sound similar way to the disk drive sound slider? The sound level is very quiet compared to STf sound and music.

[Steven Seagal]

It's not to annoy you, but is it possible to open a thread per request or the discussion becomes hard to follow?
I opened a thread here for this issue:
viewtopic.php?f=94&t=31953

[Marakatti]

It's not to annoy you, but is it possible to open a thread per request or the discussion becomes hard to follow?
I opened a thread here for this issue:
viewtopic.php?f=94&t=31953

Sorry I'll try to remember it next time.

[Steven Seagal]

No problem, I changed my mind at some point, so it could be confusing.

[Marcer]

I have one request.. maybe a bit wierd..

But.. how cool wouldnt it be, to have Chromecast Stream from Steem. for example when you watch demos etc.. is that possible even?

[Steven Seagal]

I have one request.. maybe a bit wierd..

But.. how cool wouldnt it be, to have Chromecast Stream from Steem. for example when you watch demos etc.. is that possible even?

If you want to discuss this please open an apart thread, a general thread is too hard to follow. Thx. In fact maybe this thread should be locked too?