MiniMig with AGA

[Karlos]

I have to say this is quite nice stuff. Now it just needs the 020 core.

+1

It's fair to say that an 020 compatible core would be advantageous as there has never been a vanilla 68000 AGA combination before, so compatibility may be adversely affected for a lot of AGA titles.

Still, it's bloody impressive.

[Karlos]

Cirrus and Virge were really tack-on PC parts retrofitted to Amiga. Virge was actually known  in the PC circle as a "3D Video Decelerator" meaning that the 3D rendering performance was slower than simply using the CPU.

They might be slow by PC standards, but they are way faster at productivity work than AGA ever was. Getting an RTG card was one of the best things I ever did for my Amiga.

[Karlos]

68K compatibility on coldfire has improved in more recent cores, but you are still left with trap-and-emulate for various operations. Not sure what happened to those instructions where they were implemented but with different behaviour to the 68K; they were the real killer.

[Karlos]

Just a small update. The CPU core is still clocked at 28 MHz but this time with two separate 256-byte instruction and data caches.

Clock for clock, that makes your implementation about twice as fast as a real 68020/68030

Nice work!

[Karlos]

Your work has piqued my interest with hardware description languages... Though I don't think I will be able to get my head around it, I'll stick with microcntrollers and software

I was thinking I should learn VHDL or Verilog or something too. When you think of all those "I wish I had XYZ for my old machine" moments...

[Karlos]

I just don't think I could grasp it... I'll have to look at some example code and see how it map to hardware... but I can't do stuff like this without a strong visualization of what is really happening.

-edit- What does this project use? VHDL or Verilog?

Already I'm lost:

Looks a bit like ADA

[Karlos]

Yeah, verilog looks like the ideal starting place. I guess once you are familiar with descriptions of hardware constructs, picking up VHDL may be a bit easier.

[Karlos]

Actually it's not mine, the whole CPU core was designed by Tobias. I only added caches to allow it to work at full speed. Despite it's not complete yet the job done by Tobias is excellent.

Damn fine work by all involved, then

[Karlos]

Out of curiosity I downloaded the VHDL source for the TG68K. My first reaction was, "Is that it? It's so small!"

When you consider the size of your typical software emulation implementation, it looks dinky

[Karlos]

I think the fact that the languages have defined microblocks ( I think I'm using the term properly) for basic operations (arithmetic, logic, data moving), these things have been preoptimised for performance. All one really needs to do in the TG68 core is decode the instruction, set the flags and pin signals correctly etc... Not to say that this isn't a huge achievement, just that the boring shuffling of bits is handled at a lower level, which saves a lot of space.

Viewed in those terms, so does any software implementation. You know, things like data move, logic and arithmetic tend to have operators in C

The whole tone of this post sounds negative and wrong... Try and reread it with a smile, as it's supposed to sound positive and excited...

:lol:

[Karlos]

Like most languages, ADA is what it is. Each language syntax is a jigsaw, pieces of which may be ugly and confusing, but overall build a recognisable whole where every piece has it's place and it all fits together snugly.

Objective-C, on the other hand, is like taking pieces from two wholly different, unrelated jigsaws and ham-fisting them together until they fit the same shape as the cover on the box, but is clear to anybody looking at them that they've been crudely mashed together without any real thought as the inherent incompatibilities between the two; you've got strange gaps, and overlapping bits that are bent completely out of shape. Overall it still works but it isn't pretty.

[Karlos]

The mind boggles!

:roflmao:

I'm making up the verb from the adjective:

ham-fisted, ham-handed: (Informal) lacking dexterity or elegance; clumsy

Ham-fisting, in Karlos-speak is to perform any action "in a manner that lacks dexterity or elegance, clumsily"... Not to fist someone with a Ham...

[Karlos]

Who knows what sort of thing they get up to in "that London"?

Where was the goatse guy from, anyway?

[Karlos]

Did you look at the second part?

http://opencores.org/websvn,filedetails?repname=tg68&path=%2Ftg68%2Ftrunk%2FVHDL%2FTG68_fast.vhd

Yes, that's actually what I was referring to.

[Karlos]

^_^