Messages

its nice to still see this place going! having originally registered with the ezboard ps2yabasic forums in 2003/4 then here i feel like the internet in general has turned to shit since the world moved on from forums and computers came to the mainstream.. i drifted away from forums myself not fully appreciating what we had,.. but have never felt a buzz like when we were all living in this place, if a forum came back around or just a place that resembled this place in its glory id be all over that!

hey fryer!!

you watch the 8 bit guy too  i love homebrew computers its where most of my time has been spent over the past years ive invested lots of time into understanding schematics .. z80 and 6502 architechture and how to interface with s/dram understand hardware timing and propagation delays clock cycles and all the old school peripherals uarts custom built ttl logic port latches etc its been a very fun side venture.

i built a few machines the most comprehensive being a z80 machine clocked at 20mhz with a teensy 3.5 at its heart the teensy would dynamically load my hand rolled rom at boot up and could pause the z80 and go off and address my bolted on v9958 vdp graphics card. i really need to get stuck into this again as it was coming along really nicely. i got side tracked building ben hecks portable zx spectrum lol.

if the 8 bit guy pulls his project of it looks like it could be very powerful. although im kind of on the fence as to if anyone will put the effort into exctracting the extra power out of such a machine. based on my experience with my own machine i know its own architechture inside out so can make it do things easily but wouldn't expect others to spend any real time with it, i am hopeful though as i would love for things to go back to a simpler time when programers could make a difference and on a single machine we could all share our experiments/ideas( like our ps2 days ) again.

ha!  thats brilliant fryer!

ive messed around with tangent space bumpmapping in the past but never thought of raycasting through the heightmap! it really adds a lot of variance to the texture.

i think i might give that a little go myself.

i was planning to post some stuff with my experiments on the z80. i just need to organize everything ive done into something meaningful, atm its a mess of wires and probes with loads of various notes all over my desk lol

  santa peeing the scroller made me chuckle!

merry Xmas everybody!

ive been building a z80 console computer for the past year, i call it the genioGS... its quite simple, it has an atmega acting a bit like my own custom uncommited logic chip... holding the z80 at startup while it packs my sram with machine code off an sd card then lets the z80 loose.. i made a custom graphics card with a paralax micro too this is still very raw atm and i think i might use a cortex at some point with my own oldschool statemachine stack based 3d ogl type driver for the gfx.. and the z80 can send io commands to the mega and the mega takes care of my io stuff.

all pretty pointless in the grand scheme with the way technology has progressed but i now know far more than i ever thought i would.

@kirl how did those projects progress mate? they look really really cool!!! i cant belive i have been away for soooo long.

@fryer thats awsome mate!!

how are you generating so much depth?

oh, excellent!!! i have a cool idea for a webgl entry!

hi tronkiko,

its brilliant to see you around again after so many years

i am between javascript html 5 and java for the android platform atm. i have always been a fan of portable consoles so javascript and java is now at a point of being perfect for sharing between multiple platforms, portables included.

excellent effect ck! and the code is really portable too. reminds me of a high powered microscope looking at purple bacteria. nice one, i will probably have a mess around with your values just too see what crazyness happens 

not really an amiga guy, so not sure quite what i need too view the code from that file?! is there any way that someone could do a text dump of it.. or is this just a ram dump that would need reverse engineered.

right here is my attempt from tonight. i downloaded hellfire's little alpha mask image and loaded it into my code then i just treated treat the red color channel as a distance value and draw everything up to timestep until timestep hits 255.

i did this little example in freebasic but hopefully you guys get the idea.

please ignore all the code in my main file other than this part

Code Select Expand


        dim as short x,y
        for y=0 to resY-1
            for x=0 to resX-1
                if ((alphamask->integer_buffer[x+y*resX] shr 16)and 255)<this_timestep then' if value in alpha mask is lower than what our current time step is display this pixel!
                    backbuffer(x+y*resX)=image(imgtype)->integer_buffer[x+y*resX]
                end if
            next
        next
        this_timestep += 0.07f' change this timestep to a higher value for a faster unvailing or a lower value for slower.
        if this_timestep>255 then
            imgtype+=1
            if imgtype>1 then imgtype = 0
            'change display too next sequence
            this_timestep=0
        end if


all the other code sets up a window and double buffering and loading images etc.etc which is specific too freebasic and windows. the code above is the only part that actually relates to this effect.. it takes care of swapping images and sweeping round the alpha mask etc.

this is very fast on my comp. if timestep is set too 1 it is unwatchable quick.

ive attached a rar with source, images, and exe included.

k+ emook, excellent recreation of the effect there mate!!

im with hellfire on this one though a simple hue mask and a couple of if checks is so much less computationally expensive and simpler too execute.. these demos were coded at a time where doing this effect in a geometry sort of way would have been too hard on the system.

ill try too grab an hour free in the next few afternoons and code a little example of how i belive this was done. just for fun and adding a little into mix

hey ck welcome too the forum

haha just kidding mate :p,.. yeah i think the forum is having a bit of a quiet time of it atm although i have some cool stuff im currently working on... emulators and a little 3d horror game in the vain of p.t. as well as all the usuall hardware stuff i do.

the 3d p.t. style game i am building is built on the nvidia terga development kit so i can deploy it too android or pc its quite cool. i don't post much of my projects here anymore though because i dont know if anyone is getting anything from them which is a shame.

its nice too see you around again! looking forward too your java/php stuff again!!

well after about 3 and a half weeks of debugging reading and general messing around i finally managed to get my NES emulator in freebasic going tonight!!! 







i must admit i did a little of the running man irl :p.

its all very early atm.. no sound yet and only mapper 0 rom's supported but it runs very fast and all roms seem very stable no crashes. with only a few gfx glitches on some roms tested.

i was a 6502 virgin just a few weeks ago and didn't really know what i was getting myself into untill it was too late. the nes is very very sensitive too timing and its necessary too have proper vblank setup on the ppu before correct cpu emulation/testing can happen so early phase debugging was a nightmare i ended up coding a system that loaded test.nes debug file into the emu then comparing each of my register and the pc and clockticks against each of the ones from the debug log on the fly.. then when a difference was found my emulator would break, show me the opcode that borked up and let me rewind too previous opcodes too see why and where the messups were coming from. however it was all well worth it!

now ill keep working and when audio is emulated as well as more mappers and frame clamping ill post it up for you guys to have a look at.

thanks hotshot!

this was a nice little project too get me into a nes emulator which im currently doing right now.. however ive updated the chip 8 emulator above again this is the 3rd update and it just brings lots of stability patches and little ch8 bug fixes.. im quite happy too say this is very stable and quite finished now.

maybe i should have used more pictures.....


anywho i have updated the above, tonight.. i have done loads.. now its just a matter of dropping a ch8 file into the open window and the game will start too play. similarily when changing games there is no need too shut the emulator down just drop the new game over the running game and it will change.

also added dynamic cpu scaling too hit target fps! a splash screen.. added some emulator controls ie 0 does a game reset( this was too save having too restart the emulator every time the end of a game came). 9 switches index register hack on and off i found that some games need this hack too run correctly while others don't so its easy too toggle it now. left and right arrow keys adjust the target fps adjustable from 20 fps all the way up too 300 in 20fps increments, i thought it would be best too leave this fully adjustable.

there is full instuctions in the folder describing all this and full source as well

i rewrote a lot of the cpu core got rid of lots of nasty little bugs and overall its just much tighter/nicer. ill still keep messing and anything i find ill update and repost. cheers

to manipulate a special x,y position in the 1D array, a lot of extra muls, divs, mods are required

pointers are your friend

<edit i wrote a suggestion and it was a lot of poo ..so i have revised it,  probably multicore is as good as it gets for a speedup after everything is as optimized as much as possible. you can easily split a buffer into number of cpu core segments and render too these all at the same time... with good code comes good cpu core scalability too, only downside is that with each core you decide to use you have too duplicate all your variables too give that core its own set,... or problems will happen.

hey guys.

lately i have been wanting too do an emulator. i have never done one and was always curious, so i got from thursday till today off work and decided too give emulation a blast. done a bit of reading and found the good old chip 8 interpreter was rather easy to do.

so i got stuck in and done full chip 8 which appears too work 100% correctly! i thought great! but wanted to do more so i then added superchip8 opcodes and hireschip8 got all this working with full screen scrolling, 16x16 sprites etc.

then i noticed the MEGA chip 8 documentation and demos so i added that also.

this has been fun and i still have too add a few little functions for full Mega support. however my emulator runs every demo made for the mega so far.

the keys have been mapped too our pc keyboard keys{1,2,3,4,a,s,d,f,z,x,c,v}. i have included in the archive every known chip8 mega8 super8 hires8 demo game and app! as well as an assembler that does all the systems and a few tools too convert resources into asm.

now if you wish too run games i haven't prebuilt into win32 exe's just go too the huge comment block with games in my source and change the path of one of those too the rom you wish too run then build with fb.

also i need too figure out how too get my virtual cpu too dynamically throttle its self too maintain smooth 60hz screen updates right now there is a cpu var at the top of the source that i am having too change too slow down and speed up the amount of allowable cpu cycles per second as without this some of the games run uptoo 3000fps!

there is some really good games and demos prebuilt here... me and the kids really enjoy ant, the cave, blinky, car, mega8 twister demo etc.

enjoy guys and ill update probably next sunday with any changes i make. im also planning too write my first little asm mega8 game for this. then ill be onto z80 gameboy probably.

<edit - noticed when the download link is clicked a 404 pops up from dbf?>
<edit2 - its ok ive just used my dropbox. the emulator with all games source asembler etc can be downloaded from link below cheers >

https://www.dropbox.com/s/c1tkc9ekxau1av9/Ninos%20MEGA%20M8TE%20chip8-mega8-super8-hireschip8%20emulator.rar?dl=0

the gba is still one of the most fun platforms i have ever messed around on, closely followed by the ds. its great exploring the hardware and finding all the little quirks nintendo put in there to make it punch above its weight

with the DMA thing.. its not always a good option. the dma controller makes the cpu wait so only if its large volumes of data that needs transfered/set will the halt be offset. although from what i remember the size of a screen flush was one of the times that dma was quicker than the cpu.

there is also a little setup work too use DMA for a screen clear. i had too reserve an area of memory the same size as my backbuffer at startup and 0x00 it all out then when it came time too clear screen just feed the dma controller the whole zero buffer and let it hw accelerate cpy too the backbuffer. that is probably the biggest draw back you lose some ram. so its case dependent on weather this method can be used.

i am sure i probably do have more little quirks i found on the gba, ill have a dig in my archives and see what lurks

edit
i found a nice write up on the gba dma functionality.
http://patater.com/gbaguy/oldgba/day8.htm

cheers nick

it has all gotten a lot more geeky since this, i have my little man cave now and have been locking myself away and building some weird science type shit. when i have a break through with something i jump out like doc from BTTF and get the kids too come see haha

awesome hellfire.. some mode 4 pixel bashing on the gba! years ago on an older board me and a few other guys had a similar sort of play our self's, we did a software affine textured cube, its funny that we had the same sort of timings as you where a simple screen flush took so much precious time(although with the tiny processor its understandable). if i remember correctly while i was digging through various libs at the time i discovered that you could use the dma controller for a massive memset speedup. you are probably already doing as such though.

i loved the gba, and seeing vba there makes me want too get my old console back out/dust the cobwebs off