Rapidus Accelerator (rev.1c) for Atari XL/XE

[Sikor]

@As, but this emulator run only in 65816 mode, YES? So, it is not run on REAL ATARI HARDWARE, yes? so, it is Emulator for 16-bit processor, yes? Atari XL/XE native is 16-bit? No? So, this emulator is not for 8-bit Atari, it is for 16-bit hardware emulator in native mode, not for 6502C mode, so, it works only for 16-bit computer, which are not 8-bit Ataris. And no, Atari with 65816 is not stock Atari, is modified Atari, which can go in standard mode with standard processor. Any other opinion about compatibility with stock processor and Rapidus card will be available after ending prototype by Pasiu, maybe it will be 100%, maybe only 95... Who cares?

And yes, for me Falcon with 060 is not real falcon - it is hybrid falcon

[+Larry]

Probably in 2014 or in the worst case, 2015, I predict that Atari accelerators will become available for general use. It is true that they are not really "game changers" at this time, but especially at 7 MHz they make the Atari much more responsive, especially to cpu intensive applications like compilers and assemblers. Even the snail-like performance of the Atari Assembler Editor is remarkably improved. PBI and SIO transfers can be much faster. Overall, it is very compatible, and is user-selectable to 1.79, 7.16, and 14.32 MHz with many existing Atari rom OS. I know little of the Rapidus accelerators, but I presume that they have at least equal promise. And certainly linear ram is the future, if our talented Atari programmers choose to make it so.

 

Then is the XL14 a "real Atari?" Each to his own definition of "real," but I use mine every day as my primary Atari -- so to me, it is a very, very "real."

 

-Larry

[Sikor]

But emulated, hardware emulated.

[Kyle22]

It is not emulated because the 65C816 is compatible with the 6502.

[drac030]

@Drac030: can it run in less -- mainly for testing purposes?

I looked up the code and, at some (little, maybe hardly noticeable) performance tradeoff, and risking that either the code will not fit within certain limits (causing further performance tradeoff) or I will at least not have any place for possible bugfixes, I could reduce the memory requirements by some 64k, to 576k total (64+512k). A reduction by further 64k - as for this time - would probably force me to trade 64k gain for another 64k loss, so this operation lacks sense

 

I think XL14 offers 512k total (64+448k), so a reduction from 640k to 576k would not improve anything. But I will think about it.

 

I generally planned that the program will fit within 1024k (64+960k). An earlier version required 832k, so the situation was already improved by decreasing this to 640k

[+Larry]

Thanks for checking!

 

-Larry

[Sikor]

It is not emulated because the 65C816 is compatible with the 6502.

So:

http://en.wikipedia.org/wiki/WDC_65816/65802

reset[/url], the W65C816S starts in "emulation mode," meaning it essentially behaves as a 65C02.

http://www.westerndesigncenter.com/wdc/documentation/w65c816s.pdf

The WDC W65C816S is a fully static CMOS 16-bit micropr

ocessor featuring software compatibility* with the

8-bit NMOS and CMOS 6500-series predecessors. T

he W65C816S extends addressing to a full 16

megabytes. These devices offer the many advantag

es of CMOS technology, including increased noise

immunity, higher reliability, and greatly reduced power r

equirements. A software switch determines whether

the processor is in the 8-bit "emulation" mode, or in

the native mode, thus allowi

ng existing systems to use

the expanded features.

Second link is official datasheet of 65816. It's simply said, that 8-bit mode is emulate in it. So - simply - it is emulate. So, Atari with 65816 procesor only emulate 8-bit Atari (determinate by processor type) - so it's simply emulator. Hardware, but always emulator.

Edited January 19, 2014 by Sikor

[danwinslow]

Well, as for me, I am just tremendously excited about the accelerator itself, and I look forward to writing software for it. Whether or not its a 'real' Atari or not I'd probably say it's not....but that really doesn't bother me.

[as...]

It doesn't bother me as well !!

[Sikor]

Yes, this accelerator card is great. But - it is not 8-bit Atari now, this is 16-bit XL/XE machines...

Edited January 19, 2014 by Sikor

[as...]

Sikor if you turn off your Rapidus, you will return to stock atari .
This same actions on Falcon with ct63.

 

I I have been waiting for this accelerator for many years

[Sikor]

Yes, if I'll turn it of. But, when it is on - it's 16-bitmachine, no 8-bit.

[flashjazzcat]

But, when it is on - it's 16-bitmachine, no 8-bit.

Is it?

[Sikor]

Yes, for me it is 16-bit. If not - why programs write specially for 65816 don't work on 6502C?

[flashjazzcat]

Yes, for me it is 16-bit. If not - why programs write specially for 65816 don't work on 6502C?

 

Heh... nor do programs written for other non-6502 8-bit CPUs.

Edited January 19, 2014 by flashjazzcat

[Sikor]

No,this card is o.k. and interesting, put more power for our machines. But really - it is emulate 8-bit, because it is real 16-bit machine now (in accelerate mode with 65816 or other processor than 6502 (6502C in newest machines) on.

[Beetle]

Regardless of what a Rapidus makes out of an XL/XE - i want one! I own enough stock a8, another Frankatari won't matter.

I also own a Falcon 060 with Supervidel - its still a Falcon.

 

Please get into production with the Rapidus!

Edited January 19, 2014 by Beetle

[+CharlieChaplin]

Well,

 

I guess what Sikor wants to say is that we are on a way of dividing the small A8 scene with such an upgrade even further. Remember the time when we had just Atari 400/800 computers, if they had only coded programs for 48k RAM, a lot of users would have had problems using/loading these, until they upgraded to full 48k RAM (which was not cheap, nor that easy with an Atari 400). Later the XL and XE computers were available, but imagine if from 1985 onwards there would only have been programs for 128k RAM, a lot of 48k/64k users would have been left outside alone then...

 

Nowadays we have RAM upgrades of 1MB up to 16MB available and there are programs that utilize a full 1088k RAM, even programs that will not work with less memory than 1MB. We have graphic upgrades like the VBXE and programs that will utilize that upgrade, even programs that will not work without it. In the near future we will have some more 65816 upgrades and of course also programs that will utilize these accelerators and again programs, that will not work without them. The sad thing is that whenever such hardware upgrades become available, programmers not only tend to use these upgrades, but they also quite often code programs that will only work with these upgrades and will no longer work on the standard A8 computer. Atarians with a standard A8 would have to upgrade or use an emulator then (which will most likely lead to less users of real A8 machines and more users of emulators).

 

There will never be hundreds or thousands of programs for these upgrades, so one has to decide if he really needs such an upgrade (with only a dozen or so programs available for it), but as said before this is dividing the A8 scene into several smaller groups: the ones with standard 48k/64k/128k computers, the ones with RAM upgrades and the ones with graphic upgrades (VBXE), sound upgrades (Audio-Board), speed-accelerator (65816) and other things that try to turn the A8 into an Amiga or beyond.

 

In the 80s it was quite annoying, when Atari hit the market with dozens of controllers, with a few or only a single game for each of them, looks like we are doing the same nowadays with these hardware upgrades. And err, since there are thousands of existing A8 programs, there is always at least one program, that will not work with such an upgrade and therefore requires to turn it off... not to mention, that not every of these upgrades will work alright with other hardware upgrades...

 

----------

 

My personal and fully subjective view is this:

- if I need more speed for the A8, I use an emulator and set it to full speed, thats even much faster than a 65816 upgrade (I can still use A8 Assemblers, Packers, etc. that run much faster then)

- if I need ZX80/81 or ZX-spectrum emulation or any other sort of computer/console emulation, I simply install such an emulator on the PC; I never use ZX-Emu, Apple-Emu, PET-Atari or similar emulation programs on my A8...

- if I need better sound (16 Bit stereo, surround, whatever) or better graphics (much higher resolution and more colours) I could easily buy an Amiga, STE or PC or simply install an Amiga or STE emulator on my PC with thousands of programs readily available

 

My favourite upgrades for the A8 are therefore:

- alternative OS, in my case besides the original XL-OS, I often use the old Atari 400/800 OS and with these two operating systems on an Eprom I am 100% compatible to all existing A8 software...

- RAM upgrade: having 64k RAM is nice, having 576k or 1088k RAM (switchable) is even nicer for all kinds of applications (copy-programs, etc.), games and demos

- sound-upgrade: a second Pokey chip for all those newer programs that support stereo is really nice to have - and for all older (mono) programs I use an external sound-upgrade that makes them sound stereo

- S-video: for a better picture/display S-Video is nice; but to be serious, it is already a little outdated, so I dream of another internal or better external upgrade (not too expensive, less than 100 Dollars) that will give me VGA or HDMI without the need of having a graphic-card inside the XL/XE...

 

----------

 

-Andreas Koch.

 

[flashjazzcat]

I think that's a heavily overblown analysis, I'm afraid. Some 4-5 years after VBXE 2 first became available, the number of games and applications which absolutely require that hardware are probably just getting into double figures now. It's often possible to code the same application so that it works seamlessly with or without the upgrade too (drivers help here). Likewise 1MB RAM upgrades. Are there really so many games and applications out there which require 1MB of RAM and no less? I can think of a few demos. I certainly don't see 1MB RAM upgrades cleaving the community in two. I think the very suggestion rather over-dramatises the situation.

 

You also assert that coders immediately start coding for the hardware: I haven't particularly seen this happening to a prolific degree with VBXE and 1MB RAM upgrades. It's taken years for stuff to start appearing, and most of what has appeared has had a generally positive effect on development across the board. These upgrades give interested parties a chance to take the machine in new directions, and those who aren't interested can safely keep on walking by. While it might polarise opinion, I think it's ludicrous to suggest that VBXE has actually done harm to the A8 community. I think there's a lot of great software coming out today which runs just fine on stock hardware - or certainly upgraded hardware which was around "back in the day", and does not tangibly alter the basic character of the machine.

 

Sure I might be inclined to a stick a 65816 accelerator in one of my machines some day, but this doesn't mean the whole collection instantly becomes "non-Atari". It doesn't mean I'll stop developing applications that will run on a stock 6502 A8, just as having VBXEs and Ultimate 1MBs in four of my machines doesn't mean I develop nothing but software which requires 1MB and a VBXE. I think the explosion in 65816 development which you envisage is rather overstated.

 

Just as with VBXE, let those who want a 65816 board buy one and enjoy it; it doesn't have to affect anyone who doesn't want one.

 

Honestly - you use 128KB of RAM as an example. Well, the 130XE has now been around for nearly 30 years and software is still being developed which runs in 64KB, so what's the problem?

Edited January 20, 2014 by flashjazzcat

[+Larry]

I was at Lotharek's site yesterday and looked at the Rapidus info, but I still have a couple of questions.

 

1) Is there expanded (Rambo) ram on board or only linear ram? (I did notice that it mentions: compatible with Ult 1MB, so perhaps that is a clue that there is only linear ram on board.

 

2) The "up to 30.5 MB of storage" SDRAM. How would this typically be used -- I presume it is volatile. (?)

 

-Larry

[laoo]

1) Linear RAM is on Rapidus board itself. It's orthogonal to any Rambo (or any other PORTB) memory installed in the Atari. Basically PORTB RAM is accessible in both modes (6502 and 65c816) and linear RAM is accessible only in 65c816 mode.

2) It's volatile. It's hard to imagine exact usage but nowadays it's hard to find smaller memory chips and there is no point in enforcing any artificial limits in situation when full address space can be occupied by memory with no additional cost.

[+Larry]

Thanks. I did happen to think of something else regarding the SDRAM -- if the 65C816 can only address 16 MB, how would the extra memory be used? Some type of banking arrangement or facilitated by a separate controller?

 

All-in-all, a very neat project and incredibly space-efficient use of the PCB!

 

-Larry

[Sikor]

I agree with Andreas.

[drac030]

if the 65C816 can only address 16 MB, how would the extra memory be used?

Four banks, 4 MB each, switched inside the existing address space ($800000-$BFFFFF).

[Beetle]

I agree with flashjazzcat. For me, upgrading my XL/XEs is part of the hobby, and it always was. No new upgrades, no new fun. And a working 65816 upgrade,

with linear RAM and that compatible (runs one of my favorite games in vastly improved perfomance: RoF) was always something i wanted.