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Geeky things I'm up to

Entries in this blog

 

Time, it is precious

Well, I mentally looked at the list to Leprechaun to-dos and decided that I needed to tackle the BLIT routine next. This is the code which copies the sprite graphics (running etc) from ROM to the strips of SuperCharger RAM that the kernel then uses. (Much like the 5200 & A8s.)And I'm glad I did, because I discovered (to my horror) that the routine barely fits in the time between the end of VSYNC and the start of the kernel. (Actually, I had to increase that time by a couple of lines even.

Guest

Guest

 

Fractional positioning

I just had an interesting thought. Typically with fractional positioning the fractional byte is treated as an unsigned value/256. So $10.10 = 16+16/256.   For Leprechaun I see that causing two problems. First when the sprite moves left, it will move one pixel left on the first frame (3+n/256), but it will take multiple frame to move right one pixel. Second, my collision detection only checks the integer bounding boxes, which is okay from a sprite perspective, but is a little sloppy numeri

EricBall

EricBall

 

flaws in Force Awakens (spoilers)

I saw SW VII last weekend so I could stop worrying about spoilers. While the Force Awakens is a great movie and a worthy and logical successor to Return of the Jedi, it is not without it's flaws. First is the Death Star Mark III, complete with last minute destruction (IV & VI) following an attack on the shield generator (VI), a short trench sequence (IV), and flying into the structure (VI). Even Han points this out when planning the attack; almost, but not quite, breaking the fourth wal

EricBall

EricBall

 

more Apple ][ musings

My latest distraction is the Apple ][ disk. I'm sure some of you, like me, remember the golden age of copy protection & cracking which happened around the Apple ][. Much of that was because the A2 was largely software driven. (Another Woz brilliant lunancy cost-cutting effort like A2 graphics.)   Unfortunately, because the A2 was pre-Internet, there isn't a lot of surviving detailed documentation on the web. The one piece I'm missing is a detailed description of how the bits get writte

EricBall

EricBall

 

WIP, gameplay complete

The basic gameplay is now complete. Press the button and push the joystick right or left to dig. Comments, opinions & suggestions welcome.I also managed to trip myself up quite nicely as I was adding the new sprites. Basically I forgot that any access to $1FF8 aka $FFF8 on a SuperCharger will trigger a bankswitch. And I stuck the sprite data after the playfield bitmaps, which just happened to be on page $1F00. So the game would work quite nicely until it did the right blit and accessed

Guest

Guest

 

Now with sprites!

Thanks to Ben Langberg, Leprechaun now has sprites.Thanks to Manuel & Thomas, I've managed to trim 13 whole lines of CPU time off the blit routine. I still need to work on their suggestion of changing the playfield to reflected. That will take some more effort. I also have plans to squeeze in REFP0/1 logic, which will reduce the ROM space needed to store the sprites (since right now I have to store both right & left versions).Other major to-dos (not necessarily in this order):1. Add t

Guest

Guest

 

movie studio stupidity

For those of you who aren't techo-geeks let me give you a quick summary:The big electronics manufacturers have created the successors(!) to DVDs : HD DVD (arriving March 23rd) and Blu-Ray (arriving May 23rd). Both are CD-sized optical discs like DVDs and are capable of HDTV resolution. But, because the two camps couldn't work out their differences we're stuck at the moment with two incompatible formats. Which one is VHS and which one is Beta remains to be seen.Unfortunately, most studios have de

Guest

Guest

 

Playstation 4 musings

So Sony has decided to partner with AMD to provide the processing power in the next Playstation console. They are sticking in a single chip eight x86-64 AMD "Jaguar" cores and a AMD next-generation Radeon™ based 1.84 TFLOPS graphics engine backed by 8GB of GDDR5 RAM. The single chip "APU" will likely also include a dedicated video encoding & decoding processors.   My first question is whether 8GB of RAM will be enough (although that's a leap from the 512MB of the PS3 & XBox360) - and

EricBall

EricBall

 

Next XBox will install all games to hard drive

from http://www.ign.com/articles/2013/03/20/xbox-durango-requires-all-games-to-be-installed   "Every Durango console will have a hard drive, although its exact capacity has not been chosen," reads help documentation in the Durango XDK. "It will be large enough, however, to hold a large number of games. All games will be installed on the hard drive. Play from the optical disc will not be supported."   My question is why. I can't think of anything (anti-piracy or anti-resale) which would requ

EricBall

EricBall

 

Looking for game ideas

Many moons ago I bought Civilization Revolution for the PS3 and have been playing it quite a bit ever since. But always single player, i.e. versus the AI. I've gotten fairly good, where I win the majority of the time against the highest difficulty level. But I've avoided the online multiplayer for a couple of reasons - can't save (so have to dedicate time), and there are quite a few very good players out there.   Well, this weekend I played my first online game and got spanked. Yes, at the

EricBall

EricBall

 

Apple ][ hi-res graphics

The Apple ][ was capable of "280x192 6 color hi-res graphics", but how it accomplished those graphics is bizzare to anyone familiar with modern memory mapped graphics (i.e. 256 color VGA). Even more amazing was the quality of games which were written for the Apple ][ series in spite of what the programmers must have gone through.In conventional memory mapped graphics there are two basic assumptions: 1. Each pixel is represented by a set number of bits, e.g. 1 for monochrome, 2 for 4 color, 4 f

Guest

Guest

 

Xbox One & used games pt2

Gaming sites are filled with rants regarding the Xbox One and Microsoft's decision to allow publishers to limit or restrict sales of used games.   I think Microsoft's biggest problem was not in the decision, but how they presented it. Imagine if they had presented it like:   The power of the Xbox One isn't just the boxes in your home! Xbox One games can use the power of Microsoft Azure via your broadband Internet connection to provide even more realism and deep game play.   And because

EricBall

EricBall

 

more Disk ][ musings

As I mentioned in my previous entry, I've been taking a deep look at the Apple ][ Disk ][ controller. IMHO it's an elegant blend of hardware, software & firmware.   The crux of the controller is the P6 (8bitx8bit) PROM which describes the state machine along with an 8 bit shift register and a 4 bit state register.   The CPU selects one of four modes via two PROM address bits (called Q7 Q6): 00 read a byte 01 sense write protect 10 write byte 11 load byte for write   The other 2 ad

EricBall

EricBall

 

Grand Theft Auto V

As has been splashed all over the news, GTA5 sold $800M in the first 24 hours, the most of any game and far more than any movie. I'm sure than most of the approximately 13 million copies were pre-orders, so it remains to be seen how many more sales will happen over the next month (or however long the advertising blitz continues). But in any case I'm sure Rockstar and Take-Two Interactive are celebrating.   What amazes me is with just the first day sales, GTA5 is already near the top of the b

EricBall

EricBall

 

"free to play"

Although I don't program games for a living, I visit gamasutra.com daily. A common topic in many articles is "free-to-play", from philosophical treatises to in-depth tutorials on how to best convince players to pay-up. Personally I think "free to play" is killing the industry (Nintendo being the current whipping boy) because it disrupts the most direct feedback loop between the creators and the players.   You see, IMHO players should be paying for content, because this is what the programmer

EricBall

EricBall

 

PS3 Linux RIP (for now)

For those of you with PS3s, be aware that the April 1 update disables OtherOS. So after installing the update you will no longer be able to install OtherOS or boot into OtherOS - so no more PS3 Linux. (Of course, the PS3 slim didn't have this ability.) Not upgrading means you will no longer be able to access the Playstation Network.   There has been much discussion on whether this is legal. IANAL, but I suspect it is not and Sony will be forced to either provide compensation (e.g. Playstat

EricBall

EricBall

 

Software licenses?

On the Prop front, I now have 2 to 5 COGs happily working together, alternating lines to produce a stable static screen. This is very, very cool (for me).   Next steps: 1. (Easy) fold the blank line code into the active line code. Every bit is sacred! 2. Put back in the sprite -> lineRAM code. 3. Create a demo to show it all off.   And... that'll be about it, just ready for release. Which brings me to my topic question - Software licenses.   What I want to do is release the code

EricBall

EricBall

 

Next project

While working at IBM (1993-2008) I acquired several classic Model M keyboards. Unfortunately, they have PS/2 connectors which isn't supported even by many current desktops. I have bought one of the "blue cube" adapters so I can use one at work, but I'm thinking I'd rather "roll my own" - open up the keyboard and replace the 6805 based controller with something that will output USB.   This has been done before by others, so I'm not breaking new ground. I even have a keyboard which is missing

EricBall

EricBall

 

Leprechaun Level Editor (alpha)

Announcing the Leprechaun Level Editor!   This will allow you to create your own Leprechaun levels. The SAVE button dynamically creates a SuperCharger binary (based on the current development release) usable by any emulator or SC compatible RAMcart.   I plan on adding a LOAD button as well which will allow a level created with the LLE to be uploaded for editting or refreshed with the current development release.   This is all part of my plan to have people create lots & lots of level

EricBall

EricBall

 

Apple TV 4 games - fail

Why do I say fail? Simple: no standardized controller except for the small touchpad on the remote. Why not announce a standard controller app (similar to the Remote app) or declare the PS3 or PS4 controller a de-facto standard Bluetooth controller? (Although then they'd need to provide a USB input for pairing.) This would then allow developers to port games much more easily. Heck, with a controller app Apple could provide a way for the Apple TV game to push the controller layout down to

EricBall

EricBall

 

3D TV is dead

https://entertainment.slashdot.org/story/17/01/19/2218238/3d-tv-is-dead I don't dispute that 3D TV never took off, what I find interesting is the TV manufacturers decided to drop a feature - no matter how unused. What's interesting is 3D is still popular enough to make 3D films. (Although my preference is for 2D editions I saw Rogue One in 3D because there wasn't a non-3D showing on a big screen.) Personally my 55" LG TV is passive 3D capable - so the glasses don't require batteries. I

EricBall

EricBall

 

2b2t Minecraft - starting a YouTube channel

I am going to start a YouTube channel https://www.youtube.com/channel/UCxuqdYak8Q81EUkUeSDoUVg of my 2b2t experience. My plan is to kill myself so I start back at spawn, then work out from there. Hopefully passing along a few bits of wisdom for new players and a few laughs. I'm bringing home a headset from work tonight to see how that works out. QuickTime does a great job of recording the actual gameplay at 4K then converting it down to 720p for YouTube.

EricBall

EricBall

 

mischief managed

Last entry I complained that I'd run out of space. Well, I've now managed to free up a whack-o-space, which has (at least for the moment) cured my space issues. I'm now trying to work out what the heck my enemy AI code is doing (along with some code tweaking). I'm hoping I can get a new release out in the next couple of days.   For those curious, I found the space in my kernal (of all places). Since I knew I needed a goodly amount of space (i.e. not just a few bytes), I first looked at the

EricBall

EricBall

 

7800 cycle counting

I've done some cycle counting of the display list builder for SpaceWar! 7800 and the results aren't pretty:   103 cycles per display list (25 NTSC, 30 PAL) 403 cycles per player sprite, +191 for horizontal wrap around 248 cycles per non-player sprite, +82 for horizontal wrap around 50 cycles per sprite header vertical wrap around 200+ cycles of overhead   At 114 cycles per raster, just the display list builder is going to chew through all 62 lines of VBLANK.   So, what to do? 1. Optim

EricBall

EricBall

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