Chip16 Official thread (Development/Suggestions)

[sbeng]

Ok done

[Leandro Jardim]

Hi everyone.

I am going to try some modifications on the Chip8/Chip16 instruction set. I am interested in orthogonality, an uncommon topic perhaps by being a bit theoretic, but I dont know how to do it.

I would like to know, if on the production of an instruction set, the arrangement of the opcodes is needed for the machine which its running (for dispatch optimization, etc). For example, I should order the opcodes in groups by operation (store, load...) or by operands (for example by argument count, to simplify argument decoding).

To make it clear, see this where all opcodes FLIP are grouped by the last byte:

08 00 00 00	FLIP 0, 0		Set flip orientation for sprites. horizontal flip = false; vertical flip = false
08 00 00 01	FLIP 0, 1		Set flip orientation for sprites. horizontal flip = false; vertical flip = true
08 00 00 02	FLIP 1, 0		Set flip orientation for sprites. horizontal flip = true;  vertical flip = false
08 00 00 03	FLIP 1, 1		Set flip orientation for sprites. horizontal flip = true;  vertical flip = true

Well, this is not the case, but would make sense for a machine to separate the opcodes by opcode similarity and argument count?

I hope this is not a uninteresting question...

---

Last edited by Leandro Jardim; July 17th, 2012 at 19:44..

[tronix286]

Hi all!

There are final version of my little chip16 intro: sinedots

• no more flicked (i am using sprite 320x240 for frame buffer);
• intro size is less then 4Kb (i am replaced font and string draw procedures by static sprite);
• nice "coder's" colors -))

Enjoy!

Attached Images

dots2.png (37.8 KB, 17 views)

Attached Files

sdots_final.zip (4.3 KB, 1 views)

__________________

CHIP-16 Debugger

---

Last edited by tronix286; July 26th, 2012 at 09:10..

[paul_nicholls]

Originally Posted by tronix286

Hi all!

There are final version of my little chip16 intro: sinedots

• no more flicked (i am using sprite 320x240 for frame buffer);
• intro size is less then 4Kb (i am replaced font and string draw procedures by static sprite);
• nice "coder's" colors -))

Enjoy!

Nicely done mate!

[refraction]

Nice one tronix! Now I'm back from my honeymoon I might work on finishing my crappy fighting game lol

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/

[tronix286]

Thanks refraction, paul_nicholls!
Yet another sine-table demo caled sine flag -)) For best viewing enable "Recompiler" and disable "Vertical sync" options in Refchip emulator. Otherwise demo speed is very slow (many math calculations).

Attached Images

sineflag.png (20.1 KB, 13 views)

Attached Files

sineflag.zip (2.3 KB, 12 views)

__________________

CHIP-16 Debugger

---

Last edited by tronix286; July 26th, 2012 at 09:11..

[tykel]

Originally Posted by tronix286

For best viewing enable "Recompiler" and disable "Vertical sync" options in Refchip emulator. Otherwise demo speed is very slow (many math calculations).

Disable vertical sync?? THAT'S CHEATING!!

Haha kidding, very nice as usual

__________________

tchip16 (chip16 assembler) Js16 (browser chip16 emulator)
mash16 (chip16 emulator) img16 (chip16 sprite converter)
______________________________________

Desktop: i5 750 @ 3.6 Ghz, 4GB ram, GTX 570 OC | Windows 7 Pro 64
Laptop: (Thinkpad) i5 430M, 4GB ram, Intel IGP | Arch Linux, Windows 7 Pro 64

[tronix286]

Originally Posted by tykel

Haha kidding, very nice as usual

Thanks tykel! BTW i found bug in your javascript emu. You shold declare registers array as unsigned int 16, not signed:

    r = new Uint16Array(reg),

If you fix it your emu can run mandel.c16, dots2.c16 and sineflag.c16 normaly.

__________________

CHIP-16 Debugger

[tykel]

Originally Posted by tronix286

Thanks tykel! BTW i found bug in your javascript emu. You shold declare registers array as unsigned int 16, not signed:

    r = new Uint16Array(reg),

If you fix it your emu can run mandel.c16, dots2.c16 and sineflag.c16 normaly.

Thank you, this works.

May I ask why though? The spec does say registers are supposed to be signed no?

__________________

tchip16 (chip16 assembler) Js16 (browser chip16 emulator)
mash16 (chip16 emulator) img16 (chip16 sprite converter)
______________________________________

Desktop: i5 750 @ 3.6 Ghz, 4GB ram, GTX 570 OC | Windows 7 Pro 64
Laptop: (Thinkpad) i5 430M, 4GB ram, Intel IGP | Arch Linux, Windows 7 Pro 64

[tronix286]

Originally Posted by tykel

May I ask why though? The spec does say registers are supposed to be signed no?

int16 has minimum value −32,768 and maximum value +32,767 so what happens if i multiple 160 by 320? I expect to receive 51200, right? But i get an overflow and wrong result.

Our chip16 processor uses Sign-and-magnitude method and we don't need control signed or unsigned numbers curently used. For example, at current emulator cycle we need addiction r0 and r1:
r0 = 1001 (binary)
r1 = 0001 (binary)

1001 add 0001 = 1010
What is 1010 (decimal) ? It's -2 or +10? At "hardware" level we don't know. It's controlled by application programmer, how interpreted this value.

__________________

CHIP-16 Debugger

---

Last edited by tronix286; July 26th, 2012 at 13:28..

[refraction]

right guys im going on a refchip16 fixing spree tonight, so if you know of any bugs, let me know now and ill get them sorted.

I know about not drawing the top line or the line down the left hand side, that's already fixed in the repo (altho im going to modify it again as its technically able to overflow the array atm).

If you know of any others i will get them sorted

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/

[paul_nicholls]

Originally Posted by refraction

right guys im going on a refchip16 fixing spree tonight, so if you know of any bugs, let me know now and ill get them sorted.

I know about not drawing the top line or the line down the left hand side, that's already fixed in the repo (altho im going to modify it again as its technically able to overflow the array atm).

If you know of any others i will get them sorted

Here's a bug: when I ran my Boing demo in refchip16 with the re-compiler activated, I get no graphics only a grey screen...

[tronix286]

Originally Posted by refraction

right guys im going on a refchip16 fixing spree tonight, so if you know of any bugs, let me know now and ill get them sorted.

If you know of any others i will get them sorted

Originally Posted by paul_nicholls

Here's a bug: when I ran my Boing demo in refchip16 with the re-compiler activated, I get no graphics only a grey screen...

refraction: my tip: please control SP pointer overflow (if SP => 0xFFFF then show SP overbound error message).

__________________

CHIP-16 Debugger

[refraction]

Cool cheers Guys ill do them

Tronix: what I might do for that is add a developer output mode which has a console window displaying problems. Not sure what else to add at the moment but I don't really want popups as it might get annoying

Edit: the "Boing" bug might already be fixed in the latest revision, but havent done a release yet (as i have these other little bits to do)

also im going to write a small sprite flipping test which you can move a square around, i need to test sprites going off the edges of the screen, i dont think my code is working quite correctly.

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/

---

Last edited by refraction; July 27th, 2012 at 13:36..

[tronix286]

Originally Posted by refraction

Tronix: what I might do for that is add a developer output mode which has a console window displaying problems. Not sure what else to add at the moment but I don't really want popups as it might get annoying

Yes, you're right. Debug console window is optimal way.

2all : new oldschool demo named twisting bar or simply twister ready. Still have speed issues. For best viewing enable "Recompiler" and disable "Vertical sync" options in Refchip emulator. Enjoy!

Attached Images

twister2.png (4.1 KB, 11 views)

Attached Files

twister.zip (7.6 KB, 4 views)

__________________

CHIP-16 Debugger

[tykel]

@tronix: Very nice as always I particularly like the palette shifting on the text!

I might as well post something I made a little while ago, hoping I could optimise it further (didn't!).
It's a classic oldschool plasma effect, and uses a lookup table for obvious reasons. Performance is acceptable at stock speed, but obviousdly looks better derestricted!

plasma.png

On that note, let's try to keep our demos running smoothly at 1 Mhz... there's a challenge :P

Attached Files

Plasma.zip (14.1 KB, 3 views)

__________________

tchip16 (chip16 assembler) Js16 (browser chip16 emulator)
mash16 (chip16 emulator) img16 (chip16 sprite converter)
______________________________________

Desktop: i5 750 @ 3.6 Ghz, 4GB ram, GTX 570 OC | Windows 7 Pro 64
Laptop: (Thinkpad) i5 430M, 4GB ram, Intel IGP | Arch Linux, Windows 7 Pro 64

[refraction]

These demos are very cool, but I'd like to see some more games come out

Edit as to not double post:

I've written a little test ROM which allows you to flip a sprite and move it around the screen, good for testing sprites going off the edge of the screen and again when they are flipped, i had a few bugs with this which is why i made it (one of them being i had unsigned GPR registers so X and Y co-ordinates were never less than zero)

usual keys, A and B to flip (tells you onscreen) and d pad to move about

refchip16 1.46 coming soon with all the fixes in, will let you know when.

Attached Images

flipscreentest.jpg (45.4 KB, 14 views)

Attached Files

flipoffscreen_test.7z (3.0 KB, 2 views)

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/

---

Last edited by refraction; July 28th, 2012 at 13:51..

[refraction]

RefChip16 has been upgraded to 1.46!

Should fix all known bugs plus a few i had issues with ;p

tronix286: I haven't made a new developer window, truth be told i such at WinAPI but what i have done is made it so it logs it, also logging is enabled/disabled via the settings menu now so no need to recompile the emu at all.

Grab from the usual googlecode place, enjoy ;p

(sorry for double post but it was more important this didn't get lost in my wall of text! )

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/

[paul_nicholls]

RefChip16 1.46 had gotten rid of the recompiler bug with my demo...yay!

[refraction]

Originally Posted by paul_nicholls

RefChip16 1.46 had gotten rid of the recompiler bug with my demo...yay!

Indeed I did and your demo is very impressive! You have physics and everything xD

__________________

http://www.pcsx2.net
Intel i7 920 @ 3.4Ghz, POV GTX 570 1.3Gb, 1.8Tb HD space, 6Gb OCZ Reaper PC3-14400 Triple Channel
Dont PM me for help, use the forums, thats what its for!

My Chip16 Emulator RefChip16 http://code.google.com/p/refchip16/