OldGuru

Has anybody looked at: http://www.myatari.net/ ? Castle Blast is up there... Does that mean that I have to finish it up by April? Has anybody here suggested Castle Blast to MyAtari.com ? OG.

Ok, so to make things a bit more complicated: If there are JMP instructions in various routines, the address will not be restored, right? So, if instead of using RTS, I'd use JMP (back to a place I'd want) the stack can overflow... Is that right? Not that I do that in my code, I just try to understand the limits... The actual reason that I posted my questions is that after adding some more features to my game, the text area on the screen gets corrupted... That happend on the real console but not on VSS (0.7)... Still have no idea why... Thanks, OG

What is the limit of nested subroutines in the 6502 on the 5200? What do I mean? In some cases, I have my main code jumping to a subroutine, this subroutine calls another one and so on... The uP has to retain the return address of each JSR. I'd assume that it stores these addresses (and what else?) in the Stack (where is the stack located on the 5200?). How many memory location does each JSR take ? Now, if the Stack is located in the memory such that it overwirtes some program variables, the code execution will be corrupted... How does that work on the emulators? Where is the stack located? Is there a "different" memory location for the JSR return address than the stack? ...and, yes, there are quite a few questions here but an answer to any of them could help... Thank you, OldGuru.

Looks promissing to me! Can't wait to play it. BTW: Are you going to have a demo ready for PhillyClassic? OldGuru.

quote: rather than having the side ship shoot a missile, why don't you simply increase the number of times the player must shoot it? At first, one shot destroys it, but eventually you will need 2 or 3 shots (and have it change colors or bitmap with every hit). Just my idea -- any thoughts about that? I like that approach. As you said, it is somehow easier to implement. I was thinking to add a feature that when the tank is hit, it will be pushed backwards (a bit) and then continue in its original direction... on top of that a shorter range horizontal missile will make the player's life very hard . Also, I was planning to add a mode (higher) level that the tank in actually invisible (only the music associated with it will be played) and thus make the player unaware of its exact location... BTW: I added the feature that when the tank or laser beam hit the player, the player looses a turn... Playing level 5 now becomes quite uneasy... I also added some more sounds to it - Laser beams associated sound and also a music that is played when the tank is on... Also, does anybody here plan to attend the NAVA meeting on Saturday? OldGuru.

quote It is not so easy to implement this feature... specially, as things are implemented now... I like the current way of the beams appear on the screen... They really make the player's life harder... quote Correct. This will require some additional coding but there is no other way around it... quote Currently, the laser beams strike follow a predefined pattern. I might change that to be random in the future... I need to implement the vertical laser beams first... quote I have it on my to-do list for a while now... Quite non-trivial thing to do the way I implemented the castle and the way I detect the player's missile hit... quote This is why I'm looking for your feedback... Thanks, OldGuru.

quote Correct. The game never ends... I'm planning to add one more level of difficulty where some additional vertical beams come down from the castle. This way the player can't just stay in the center when the diagonal beams are activated. I was also thinking to have the tank shooting at the player but that seems to be quite difficult to do... I still have not gave it a deep thought though. If anyone has ideas how to improve the game please feel free to post. I can't promise to implement them all but will consider the ones that I feel that would be reasonable to implement. quote Agreed. There are even more bugs... I'm planning to complete coding the whole features-list I have and then switch into "bug-fixing" mode which, will eventually bring me to the finish line... BTW: Indeed, the player has to shoot at the center of a brick to destroy it. It is the way I wrote the brick-hit detection routine... which I spent quite a lot of time to code... I'm not planning to change that one... quote I'm actually using both a formula (very simple one) and a table. When a collision is detected, s_CheckHits is called. This subroutine checks all the possible collisions in the game. If a collision is detected, another subroutine is called to handle that type of collision. This subroutine calculates the RAM location, changes the color of it, updates the score and set the sound flag. quote In the version you are playng, the beams are not harmful to the player. It is foreseen to have them deadly to the player if touching them... The sound was added to it as well (sounds like a thunder)... I was thinking to start the sound 1 sec. before the actual beam comes down... this will hint the player of the fact that a dangerous laser beam will appear (somewhere) soon... quote I like that idea. I'll look into implementing it (maybe in higher levels?). Definitely will add to my to-do list... Thank you all for taking the time to look into it and post your comments, OG.

quote I'm using this version of the emulator as well. I've tried it on two different PCs. On the faster one (P3, 733MHz) it sounds sometimes messed-up, but always it is very fast (same with the game-play itself). On a slower PC (P2, 166MHz) it sounds way better although sometimes it is not... I always use the -limit option. One thing that I can promise is that on the real console is really sounds great Thanks, O.G.

Okay, so here it is... "Castle Blast" web page Go to the Demo Versions section and download Ver0.3... Some basic instructions (controls) are described on the web page... Note that this is a demo verion only! Not all the features are there yet... Also, just make sure to set -limit when you run VSS to ensure the correct speed... Enjoy, O.G. [ 02-14-2002: Message edited by: OldGuru ]

quote Yes, we will... O.G.

quote I have a "to-do" list that never gets shorter , I plan to share it on my web site soon... Currently I keep it in the source code of the game itself... When will it be ready? I hope (and try) to shoot for CGE 2K2, in which, I plan to attend this year... quote I just did it 2 days ago. The previous (free)server prevented downloading of the example code and added some more restrictions that forced me to look for something else... quote Agreed. This is why I did it this way. Personally, I like shooter games and like it even more when I (an average- player) can make nice progress through the game in a reasonable time frame. If desired, I could post the demo version on my site so you guys could try it out on your emulators (VSS 0.7 works for me, have no idea about others). Anybody interested? Thanks, O.G.

It has been a while since I last posted in this matter... The game now supports 5 levels (see description on web page) with some additional features (Castle beam - Level 5 etc.)... Some picture are available here: "Castle Blast" web page Also, note that the tutorial page works fine and all files can be downloaded as well... This www is located on a different server than the original one... No more ads. and annoying restrictions for now... O.G.

Very Nice! Would like to see a mode where an ASM code comes out of this utility. This ASM code can be later just included in any ASM/BAS file and just get enabled when the music is needed... Also, the output can be used on NTSC consoles only? Is there a mode to select between NTSC vs. PAL? Any inention to support drums in the future? One thing I can tell you for sure is that I'm going to use it from now on... Any idea where can I find MIDI samples of shooting sounds, laser guns, etc. ? Thanks, O.G.

Looks great! The more programming support (languages/tools) there are, the more new people will try to create new programs/games for it... When is the C compiler for the 5200 is coming out? O.G.

The readme file that comes with VSS mentions the unsupported games and/or some issues with "special cases"... You may find some information about how to make (some of) them run in that file. O.G.

You may want to check in "De Re Atari" as well, they have a very good description of that. Also note, that the address may change based on the missile mode you have set... O.G.

Has anybody used the feature to remove the automatic ATRACT mode? I need it disabled as the gameplay becomes longer and longer... I've been looking into the BIOS code, and it seems to me that if the main loop ensures that the value in the ATRACT address ($04) is positive ( >=0 ) this mode will be disabled. Based on that, I set address $04 each and every VBI to $01 until the game is over... It seems to work as expected but I'm not sure that this is the way it was supposed to be done... Any idea? Thanks, OldGuru.

I'm using the Pocket Programmer and their EPROM emulator - Pocket Programmer Link Generally speaking it is a good product. The biggest disadvantage of it is the old DOS program that operates it... BTW: Another approach that works just fine for the Vectrex guys is to create a non-voletile SRAM based cartridge (aka VECRAM). On one side it hooks up to the PC via the parallel port, on the other side it has the pinout of a cartridge. Once a BIN file has been downloaded into the SRAM it will stay there till a new file overwrites it. The VECRAM costs no more than $100... Although it can be directly used, it could be a nice idea to implement for any other cartridge based console... O.G. [ 01-10-2002: Message edited by: OldGuru ]

Burning an EPROM takes up to 1/2 a minute (depending how big is your code)... Downloading the code the an emulator take a few seconds - works great for me, in that case I burn my EPROMs only when going away from my computer... O.G.

OK, It was my console! I got a new one last weekend (my old one is completely out of order) and had a chnace to test the upper fire button code. Both known (to me) ways did work: 1. The VBRK interrupt is taking place when the upper fire button is pressed. 2. Checking bit D3 (If I remember correctly) of SKSTAT does reflect the status of the upper fire button. I use this method in my game now... Hope that clears some confusion in respect to this matter. DEBRO - Thanks for your help on that one. O.G.

A wild guess... You may write the HITCLR register too early in some cases... this clears all the collision bits and you may miss some of them that way... I'd make sure the the write to this register is taking place in only one place throught the whole program (no matter how many collision you are trying to detect)... Hope it helps, OldGuru.

I've been trying to use the upper fire button without success so far... I tried the "SHIFT" approach (SKSTAT reading)- that works on the emulator but not on the real console (tried with 2 different controllers)... Then, I tried to use the VBRK interrupt to handle that but again without success (it seems that my interrupt routine was never called although I eneabled it...) Does anybody has any idea? Any hidden register's bit I need to set/clear somewhere? Any help is appreciated, Thanks, OldGuru.

There is a mistake in Jay's description on his web site. However, I can't remember exactly where... I also tried it and it did not work... I had to make 2 changes for his design... one was to hook OE of the EPROM to GND, I can't remember the second change though... I'll try to look in my notes and see if I find something... Alan Davis sent me once text format instructions but I lost them somehow...

I completed all the examples on my tutorial page and they are available for download now. Feel free to use them as needed and start creating your own games now... Moderator Edit: Ronens page is located here: http://members.bellatlantic.net/vze2j83t/

Ok, So to that we'll need a long nosed plier and a large flat dcrewdriver. Grab the metal piece beteen the black rubber and the plastic handle. Then, instert the screwdriver between the plier and the plastic handle. Next, rotate the scredriver in an effort to remove the plastic handle... In my case the whole stick came out, the plastic handle was still attached to the metal piece. Now, replace the black rubber and put everything back to its original place. Hope you can figure out what was I trying to say...