3D - F030 vs Amiga 1200

[galahad]

On eab I ask them to point me to best A1200+FastRAM 3D demos since I have trouble to find these kind of demos since almost all demos on A1200 require accelerator.

That is very true and it is just another proof that stock A1200 is not taken seriously even by the Amiga users. Most Amiga user says "A1200" but in fact they mean a 68060 machine with a plenty of FastRAM.

Its not that people don't take the A1200 seriously as a stock machine, its still pretty capable, but when the A1200 came out, it was being directly compared to modern PC's (which it was already behind), and the demo scene not wanting to be left behind had big PC productions to compete against, and a stock A1200 simply wasn't going to last long. Fast ram was the norm for a lot of A1200 owners and that delivers a decent speed boost for certain code applications, and then processor cards got cheap enough that demos started using them.

Very few Amiga owners have an 060 card. I would say the most common configuration is A1200+Fastram+030card+hard drive, and thats decent enough.

The A1200 is alright, but with not much money spent on it, it was so much better.

[mc6809e]

I see. You probably have a very fuzzy idea what the DMA really is and why it has nothing to do with a separate BUSes at all. There is really only one data BUS between all chips and ChipRAM (see schematics if you don't believe me). When the CPU or DMA access the BUS, all other chips have to wait.

Actually THERE IS a separate bus called the register bus (I'm surprised you didn't see this while scrutinizing the schematics). It's used to move data into chip registers

maybe I am wrong but RGA is address bus?
and there is only one data bus to chip RAM (as ctirad stated)?

Oh, right. Sorry. Yeah, there is just one data bus, but it runs at twice the rate at which the CPU can read/write so its pointless to have two separate data busses. Simply multiplexing the bus is sufficient.

Technically there's also one address bus to DRAM, too. But again it runs at twice the speed of a CPU memory access cycle.

The point of the RGA is to address chip registers simultaneously while DMA is occurring so that data moves directly from/to an arbitrary location in chipram to/from one of something like 50 or so chip registers in just two CPU cycles.

If you see the chip registers as a range of special memory to be filled/read to/from DRAM then it becomes obvious how a second address bus helps speed data movement. (EDIT: compare how the STe's blitter writes to palette registers EDIT2: not implying the Amiga's blitter can do that. Just for illustration).

Without a second bus, one alternative is to read data from chipram and then do a separate write cycle to get the data into the appropriate register.

[Frank B]

Thats not entirely accurate. TAS is a special condition, it has three phases, read/modify/write, and most instructions are expected to only do read/write. Because of this extra condition, its 'possible' that the Agnus chip might also be trying to access chip memory during the same DMA cycle as the TAS instruction is trying to write, and invariably what happens is it causes TAS to simply not write its results properly.

Of course using TAS in registers is fine, and use of BSET instead of TAS overcomes the problem of TAS being unreliable.

bus lockouts are rare, but then most people simply didn't use it, so it was never really an issue.

It was pretty easy for me to reproduce that back in the day

Frank

[ctirad]

Its not that people don't take the A1200 seriously as a stock machine, its still pretty capable,

No so pretty. The main problem is the limited RAM size for a prodution work in workbench. It was limited like 512kB A500 before.

Very few Amiga owners have an 060 card. I would say the most common configuration is A1200+Fastram+030card+hard drive, and thats decent enough.

I know very few Amiga users which don't have 060 or at least 040. 030 + FastRAM was typical 1990s setup.

[ctirad]

Oh, right. Sorry. Yeah, there is just one data bus, but it runs at twice the rate at which the CPU can read/write so its pointless to have two separate data busses. Simply multiplexing the bus is sufficient. Technically there's also one address bus to DRAM, too. But again it runs at twice the speed of a CPU memory access cycle.

Which is same as on ST, just to be precise. And in the Amiga case the heavier DMA usage (bigger screen sizes and color depths) still eats the cycles originally dedicated for the CPU.

The point of the RGA is to address chip registers simultaneously while DMA is occurring so that data moves directly from/to an arbitrary location in chipram to/from one of something like 50 or so chip registers in just two CPU cycles.

Yes, without that they would probably did not achieve the desired level of synchronisation.

[Flash951]

By using the blitter to do vectors instead, the Amiga get's faster than when only using CPU. The Falcon specs looks very very good on the paper, but the Falcon had hardware flaws that meant they couldn't be used to their full capabilities. Like having a Porsche with a Citroen 2CV engine under the hood!

[Flash951]

No so pretty. The main problem is the limited RAM size for a prodution work in workbench. It was limited like 512kB A500 before.

This is wrong. Amiga 500 had 512 Kb internally, and 512 Kb in the trapdoor, 1 Mb was the most common. I had 7 Mb and SCSI Hard drive in my 1987 - A500 because I expanded it for productivity. When A500 was released, the A2000 was also released for productivity and great expansion abilities. The A500+ has 1 Mb internally, and normally 1 Mb or more under the trap door, 2 Mb was the most common setup for gamers. On the A1200 discussed in this thread, 128 Mbyte can be added. 130 Mbyte in total. How much on F030, 14 Mbyte?

[EvilFranky]

No so pretty. The main problem is the limited RAM size for a prodution work in workbench. It was limited like 512kB A500 before.

This is wrong. Amiga 500 had 512 Kb internally, and 512 Kb in the trapdoor, 1 Mb was the most common. I had 7 Mb and SCSI Hard drive in my 1987 - A500 because I expanded it for productivity. When A500 was released, the A2000 was also released for productivity and great expansion abilities. The A500+ has 1 Mb internally, and normally 1 Mb or more under the trap door, 2 Mb was the most common setup for gamers. On the A1200 discussed in this thread, 128 Mbyte can be added. 130 Mbyte in total. How much on F030, 14 Mbyte?

FFS. Another thread destroyed.

The A1200 could NOT address more than what 10MB of RAM, 2 chip + 8 in the trapdoor?? Without a RAM AND CPU card.

We couldn't care less about the A500, A2000 or any other Amiga model as this discussion is PURELY for F030 vs A1200 bog standard for 3D calc...which you can't seem to comprehend.

[Cyprian]

By using the blitter to do vectors instead, the Amiga get's faster than when only using CPU.

on a game console field amiga had some advantages (like blitter). But the ST was much more than a game console, it was real computer.
And on that field the ST had much more advantages than amiga, like more computing power, better video resolution, more ram, hard disk support ect. Therefore there is no need to degradate the ST to a game console level.

The Falcon specs looks very very good on the paper, but the Falcon had hardware flaws that meant they couldn't be used to their full capabilities. Like having a Porsche with a Citroen 2CV engine under the hood!

yep, it has a some flaws, but it's still better than A1200/A4000. It has better memory performance, better CPU, better sound, better video resolutions, more colors ect...
amiga has only one really small advantage, 24bit palette vs 18bit in Falcon

[Flash951]

The A1200 could NOT address more than what 10MB of RAM, 2 chip + 8 in the trapdoor?? Without a RAM AND CPU card.

We couldn't care less about the A500, A2000 or any other Amiga model as this discussion is PURELY for F030 vs A1200 bog standard for 3D calc...which you can't seem to comprehend.

I agree I was wrong about the A1200 and RAM expansion. A stock A1200 can "address" 16 Mb RAM + 2 Mb chip.
You can fit 8 Mb under the trapdoor, and 4 Mb in the PCMCIA slot and maybe some upgrades other places, but the PCMCIA slot is only 16 bit, so RAM update there makes the A1200 even slower than when only CHIP RAM is used.

[Flash951]

By using the blitter to do vectors instead, the Amiga get's faster than when only using CPU.

on a game console field amiga had some advantages (like blitter). But the ST was much more than a game console, it was real computer.
And on that field the ST had much more advantages than amiga, like more computing power, better video resolution, more ram, hard disk support ect. Therefore there is no need to degradate the ST to a game console level.

The Falcon specs looks very very good on the paper, but the Falcon had hardware flaws that meant they couldn't be used to their full capabilities. Like having a Porsche with a Citroen 2CV engine under the hood!

yep, it has a some flaws, but it's still better than A1200/A4000. It has better memory performance, better CPU, better sound, better video resolutions, more colors ect...
amiga has only one really small advantage, 24bit palette vs 18bit in Falcon

You've obviously never used an Amiga to others than games, and are missing some basic knowledge about this platform.

[Cyprian]

You've obviously never used an Amiga to others than games, and are missing some basic knowledge about this platform.

check me on http://eab.abime.net

It seems that you don't know neither amiga not Atari hardware and developer specs

[shoggoth]

It seems that you don't know neither amiga not Atari hardware and developer specs

The guy is a true believer, troll or whatever. Noticed how he never quite responds when faced with facts, and instead just moving on barfing the same thing up over and over?

[calimero]

By using the blitter to do vectors instead, the Amiga get's faster than when only using CPU. The Falcon specs looks very very good on the paper, but the Falcon had hardware flaws that meant they couldn't be used to their full capabilities. Like having a Porsche with a Citroen 2CV engine under the hood!

please continue this discussion in appropriate forum/thread: http://eab.abime.net/showthread.php?p=976025

btw Mb are mega bits. MB are mega bytes.

[ctirad]

This is wrong. Amiga 500 had 512 Kb internally, and 512 Kb in the trapdoor,

That's what I said. The stock machine has 512kB and one had to buy an expansion (or to buy and solder DRAM chips directly to the motherboard like I did) to have a 1MB that was considered as standard.

On the A1200 discussed in this thread, 128 Mbyte can be added.

No way without an extra CPU card. A1200 has 24bit address bus only, so 2MB chip RAM + 8MB in trapdoor + maybe some more in PCMCIA, but not continuous, because PCMCIA shares the same 4MB address space with the upper 4MB in the trapdoor. The 14MB of continous chipRAM in F030 is a breeze. Plenty of room for lot of truecolor bitmaps and high wuality 16 bit samples directly accesible by DMA.

[ctirad]

I agree I was wrong about the A1200 and RAM expansion. A stock A1200 can "address" 16 Mb RAM + 2 Mb chip.
You can fit 8 Mb under the trapdoor, and 4 Mb in the PCMCIA slot and maybe some upgrades other places,

It is a bit more complicated (see above for a note about PCMCIA RAM). The 020 in A1200 has 24bit address BUS, that means it can address a 16MB space. But there is also a ROM, I/O area and some reserved space that need to be addressed. So the 10MB of total RAM seems about right.

[Flash951]

To add Fast RAM in the PCMCIA on the A1200 is cheap, but will make the A1200 even a little bit slower than stock when using only CHIP RAM. Because the PCMCIA are only 16 bit.

[joska]

To add Fast RAM in the PCMCIA on the A1200 is cheap,

Where can I get this cheap? I was looking for 2 or 4Mb SRAM-cards for my A600 but they were so expensive (maybe €150-200 for 2Mb cards!) that I quickly dropped that idea.

[Flash951]

Check Amibay or Ebay, maybe 10-15$, if I don't remember wrong. Usable for A600, but slow for A1200.

[joska]

Cheapest 4Mb PCMCIA SRAM card on eBay now is around £60. The "cheap" ones are mainly 256 and 512Kb cards.

[Frank B]

Cheapest 4Mb PCMCIA SRAM card on eBay now is around £60. The "cheap" ones are mainly 256 and 512Kb cards.

Cheaper to just buy one of the individual computer accelerators

[Flash951]

Strange, because this is old PC laptop parts. Have seen them real cheap. Maybe pu ad under Amibay wanted forum.

[dml]

I mostly avoided this thread because it doesn't involve much discussion about 3D, or examples for comparison. But a couple of things I found incorrect.

68030 is faster than 68020

Actually the performance is very similar - almost exactly the same. The 030 datacache can be helpful - if used with great care - but it's difficult to use properly and in many cases slows the machine down when left on, because it is always fetching longs even if words are being requested (over the 16bit bus). Particularly painful if you're not accessing words contiguously. In the majority of cases programmers just turn it off.

So I don't see any magical benefit to having a 68030 without additional effort to make use of the d-cache properly. Slightly higher clockrate - sure, but the chips themselves are not much different in terms of speed. Cycle sheets are nearly the same.

and pure 3D graphics has to be done with CPU as both systems misses pure 3D hardware (Falcon got DSP, but some limitations for practical use and speed).

3D graphics don't have to be done with the CPU. The Falcon's DSP has a 2-cycle multiplier (or 1 cycle @ 16MHz if you cancel out the MHz ratio). It doesn't really make sense to perform 3D operations with the CPU if you have access to that. 3D is largely about multiplies.

The real problem with the Falcon at the time wasn't technical limits (although there are some of course - but it was good for the time) - it was more to do with the learning curve, the relatively small number of people who made stuff for it, and the fact it was already overdue as an upgrade to the ST.

[Flash951]

I'm aware a good programmer can get some additional speed by taking use of the DSP, but the real life speed increase compared to just using the 030 instead is not that extreme that some Atari ST fanatics claims it is. And when the DSP are being used, it has some down sides, like slowing the RAM bus ore something else down, so other stuff that might are running at the same time will suffer. That's my understanding after reading what I can here and there. I have not had an F030 to experience with myself, I've just have a normal Atari ST.

[Frank B]

I'm aware a good programmer can get some additional speed by taking use of the DSP, but the real life speed increase compared to just using the 030 instead is not that extreme that some Atari ST fanatics claims it is. And when the DSP are being used, it has some down sides, like slowing the RAM bus ore something else down, so other stuff that might are running at the same time will suffer. That's my understanding after reading what I can here and there. I have not had an F030 to experience with myself, I've just have a normal Atari ST.

The DSP does not slow down the CPU. It has its own separate RAM.