Another very early WIP

[NIKON]

well it could be made to utilize controller #2 for real hardware...which is what the 2600 version of Stargate/Defender II does in its controller scheme.

 

now this begs the question of how to manage two proline controllers....certainly cannot do it Robotron 2084 scheme...need the two buttons on the controller.

 

OR

 

Thrust and reverse would be handled by the first controller ala Joust controller scheme. Button One fires the Laser.. button 2 smart-bombs..but that still leaves hyperspace....hmmm this is getting a bit complicated.

 

OR

 

a special controller is fashioned that has a Y lead to plug into both controller ports and the controller would have the scheme of the arcade...(this suggestion not likely)

 

 

Those who use emulators would not have a problem with controller schemes and can map any button to do anything they desire...which then Defender can be programmed to use the console buttons and the difficulty switches (which Trebor posted earlier) ala Tomcat F-14 is programmed. (but this really does not help the real hardware users)

 

There are things for Bob to consider but in the end he will produce an outstanding title as always.

[Dauber]

Seems to me that a keypad would be a great controller for this...

[RevEng]

Seeing the post here, it looks like the 2-button support is coming from B and C for the 2600. A stock Genesis controller maps B (One button) only under the 7800, with an adapter B and C are utilized under the console. I'm not seeing how A (or Start) can possibly be utilized without hardware modification, but someone else (like RevEng ) can provide better insight of the option(s) if there is a way to do so.

Yeah, without hardware modifications the other genesis buttons aren't available. The +5V source line is directly connected to the genesis multiplexer's select line, which is normally used to switch between different sets of inputs. Without the ability to toggle that select line, B and C is all you can get.

 

I posted a cheap controller modification that could be used for reading 4 buttons (A,B,C and Start), and likely the other 3 buttons on a 6-button controller. But unless the intent is to bundle the controller with the game, I don't think it's worth supporting this.

 

I'd rather see the game allow the user to select between 2 different schemes. The first would utilize the buttons on the second joystick, as others suggested. The second would utilize/abuse the new controller-based select and reset standard. This would work out-of-the-box with CPUWIZ's adapter, and could easily be added to other controllers with switches and diodes.

[+Random Terrain]

I'd rather see the game allow the user to select between 2 different schemes.

Hopefully a third selection too for those who just want to play with one original 7800 controller.

[Rybags]

Found a site with reverse-engineering info on a bunch of arcade and 2600 games. The amount of info per game is somewhat variable. Space Invaders gets a nice disection but some of the others barely scratch the surface.

 

http://www.computerarcheology.com/wiki/wiki/Arcade/Defender

 

I've also got 2 books from the 80s about beating arcade games, I know at least one of them has Defender, I'll get some photos of the pages and put them up later.

[phattyboombatty]

 

 

Yeeeeeeeessssssss!!!

[+Stephen]

Found a site with reverse-engineering info on a bunch of arcade and 2600 games. The amount of info per game is somewhat variable. Space Invaders gets a nice disection but some of the others barely scratch the surface.

 

http://www.computerarcheology.com/wiki/wiki/Arcade/Defender

 

I've also got 2 books from the 80s about beating arcade games, I know at least one of them has Defender, I'll get some photos of the pages and put them up later.

I think it's so cool that the engine control computer in my 87 Daytona uses a 6809 CPU. I wonder if it could be hacked to run Defender

[Lynxpro]

Here's the Arcade control panel:

 

defender_panel.png

 

We have five in-game buttons. Two of the buttons (Reverse and Thrust) are handled by the joystick. Fire would obviously be handled by one of the two joystick buttons.

 

We're sort of putting the cart before the horse here; however, if/when Bob develops the game further along, for it to work with a standard 7800 controller, hyperspace or smart bomb can be handled as Random Terrain suggested.

 

Additionally though, perhaps as a menu option or difficulty switch setting, Fire, Smart Bomb, and Hyperspace functionality can be configured.

 

For example:

Left Difficulty Switch - Toggles whether Fire is Button 1 or Button 2.

A = Fire = Button 1 / Smart Bomb & Hyperspace Button 2.

B = Fire = Button 2 / Smart Bomb & Hyperspace Button 1.

 

Right Difficulty Switch - Toggles how Smart Bomb and Hyperspace are handled.

A = Smart Bomb = Quick press / Hyperspace = Hold press.

B = Hyperspace = Quick press / Smart Bomb = Hold press.

 

My personal opinion is menu options are probably best, as there's need to recall (or set) switch positioning.

 

As CPUWIZ mentioned, utilizing the plethora of available options via his PS2 adapter would be sweet as well.

 

 

Support for a Genesis 3-button controller would call for another adapter (redesign). The currently available product in harmony with the schematics out there, configures it so two buttons are utilized. Usually, the A button, as well as Start, do not function as a valid input for the 7800.

 

A stock Genesis controller behaves like a one-button (2600) joystick when connected to the 7800.

 

Use the 2600 Star Raiders keypad - or the regular 2600 keypads - in Controller Port #2 for the extra button options. It wouldn't be elegant but it would get the job done.

[Lynxpro]

I think it's so cool that the engine control computer in my 87 Daytona uses a 6809 CPU. I wonder if it could be hacked to run Defender

 

The 7800 can use other CPUs in its cartridges so in theory, one could put a 6809 into a cartridge and possibly run some of the arcade code. Of course, you'd need a capable PCB like CPU Wiz's wares to accomplish that…shame Atari Inc/Corp didn't do that back then.

Edited January 25, 2015 by Lynxpro

[Trebor]

 

Use the 2600 Star Raiders keypad - or the regular 2600 keypads - in Controller Port #2 for the extra button options. It wouldn't be elegant but it would get the job done.

 

Personally, I do own two regular 2600 keypads, although not sure how many others do as well; especially 7800 specific users. Besides, we're looking at only one extra button. If controller port 2 is being utilize, may as well just keep it stock 7800 controller button/input.

[Jinks]

I have a couple of them keyboards too but it would be awkward. The hold down button 2 would be better. It would be like wait for it NOW!

[+-^CrossBow^-]

A suggestion for extra button functions if this hasn't been suggested already...

 

What about one button for laser fire, the other for hyperspace, and then hold down either button while quickly pressing up or down to activate smartbombs?

[+Random Terrain]

A suggestion for extra button functions if this hasn't been suggested already...

 

What about one button for laser fire, the other for hyperspace, and then hold down either button while quickly pressing up or down to activate smartbombs?

No need to press up or down:

 

Push the second button quickly for one special ability and hold it down longer for the other special ability.

[RevEng]

Whatever the solution, Bob should probably plan ahead for "inviso" support, in addition to smartbombs and and hyperspace.

[+Random Terrain]

Whatever the solution, Bob should probably plan ahead for "inviso" support, in addition to smartbombs and and hyperspace. |

For the original 2-button Atari 7800 stick selection, blow everyone's mind with a quick click for one special ability, a longer press for the second special ability, and a double-click for the third special ability.

 

[That's only for the second button. The first button would only be for shooting. The second button would be for special abilities.]

 

Example:

 

Fire Button #1:

 

Fire. (Hold for rapid-fire.)

 

 

Fire Button #2:

 

Smart Bomb - Quick press and release of button #2.

 

Hyperspace - Hold button #2 for at least 1 second, then release.

 

Inviso - Double click button #2. [in case it's not obvious, this would only be used in the sequel.]

 

[Assignment order not set in stone. It's only an example. Hopefully the game would let the player select the order.]

[+-^CrossBow^-]

Now see I don't much care for the double button or hold etc option. I would rather be able to hold the button down for rapid fire instead. Though the one issue I can see with my suggestion is that you would always be moving up or down while firing...ugh. Using the difficulty switches isn't a good idea either since they can be a pain to get to located where they are.

[+Random Terrain]

Now see I don't much care for the double button or hold etc option. I would rather be able to hold the button down for rapid fire instead. Though the one issue I can see with my suggestion is that you would always be moving up or down while firing...ugh. Using the difficulty switches isn't a good idea either since they can be a pain to get to located where they are.

The original 7800 controller has 2 buttons. One button is for firing and that's all it would do. The second button would be for the special abilities.

[Rybags]

I found the Winner's Book of Video Games available to view online. https://archive.org/details/Winners_Book_of_Video_Games

The guide to Defender starts on page 33.

 

Wasn't able to find an eBook version of How to Master the Video Games.

 

An entire book on Defender - The Video Master's Guide to Defender. https://www.digitpress.com/library/books/book_vmg_defender.pdf

 

I should think the info in this lot should list any quirks you might like to reproduce.

The History panel of Mame has some useful info as well:

 

 

 

Defender © 12/1980 Williams.

Defender sees a single player charged with the mission of protecting the Humanoid race - who are currently stranded on an alien planet - from their alien abductors in this legendary, side-scrolling shoot-em-up. Each of the game's levels are occupied by a large number of aliens that will try to capture the Humanoids from the planet's surface and take them to the top of the play area; if an alien succeeds in carrying its victim out of the level and beyond the player's range, the captured Humanoid will mutate into an alien and join them in their assualt on mankind. If an alien is destroyed AFTER it has captured a Humanoid but before it reaches the top of the play area, the Humanoid will fall towards the ground and must be captured and returned to the planet's surface before they fall to their death. An on-screen scanner aids the player in showing the location of the many aliens and their ships in relation to the player's current position.

The challenge becomes more intense as the action progresses, with fighter ships (Bombers) and mines further testing the player's skills. A direct hit will destroy a mother ship (Pods) but will cause it to break into a swarming mass of mini-ships (Swarmers) which also must be destroyed. If the player does not act quickly enough, the Cosmic Baiter will attack. As well as the ever-present laser, the player's ship is also equipped with a limited number of 'Smart Bombs' - although their power is limited - and a 'Hyperspace' function, which will warp the player's ship to an unknown part of the level. If all of the Humanoids are abducted, the entire planet will be destroyed.

- TECHNICAL -

Board Number : D75 (top), D71F (A)
Prom Stickers : DF

Main CPU : M6809 (@ 1 Mhz)
Sound CPU : M6808 (@ 894.75 Khz)
Sound Chips : DAC (@ 894.75 Khz)

Screen orientation : Horizontal
Video resolution : 294 x 239 pixels
Aspect Ratio : 4/3
Screen refresh : 60.00 Hz
Palette Colors : 16

Players : 1
Control : 2-way joystick (UP and DOWN)
Buttons : 5
= > THRUST, FIRE, REVERSE, SMART BOMB, HYPERSPACE

- TRIVIA -

Along with Namco's seminal "Pac-Man", Defender shares the title of ''Highest Grossing Video Game of All Time'' and to date has earned more than one billion dollars. It's interesting to note that when the now-legendary shoot-em-up was first shown at a 1981 Chicago arcade machine trade show, it was deemed to be a flop due to its high level of difficulty. Arcade industry insiders confidently predicted that both Defender and "Pac-Man" would be commercial flops and that Namco's "Rally X" would be the next major arcade success.

Defender's attract mode for the game was programmed in just five hours.

Defender was noted for both its superb sound and visual effects and, moreover, for its extremely demanding gameplay. This didn't, however, stop players from accumulating millions of points when playing the game. Just minutes after the opening of the AMOA - an arcade industry trade show - Eugene Jarvis and his team - Defender's creators - were burning new ROMs for the game's display due to the fact they plugged the first burn into the board BACKWARDS and fried them. Due to the intimidating controls, hardly anyone at the show played the game and there were even rumours circulating suggesting that both "Pac-Man" and Defender would flop and that Namco's "Rally X" would be the next big hit. Not only did Defender have the highest number of controls (five buttons, in addition to a two-way joystick) but it was also the first video game to feature an artificial 'world', in that game events occured OUTSIDE the on-screen viewing area presented to the player.

Chris Hoffman holds the official record for this game on 'Marathon' settings with 79, 976, 975 points on January 1, 1984.
Gino Yoo holds the official record for this game on 'Tournament' settings with 230, 125 points.

Some bootlegs of this game are known as "Star Trek 1981", "Defence Command", "Defense Command", "Zero" (Jeutel), and "Tornado" (Jeutel).

Defender inspired a catchy hit song by Buckner and Garcia called ''Defender'' released on the ''Pac-Man Fever'' album.

A Defender unit appears in the 1983 movie ''Terms of Endearment'', in the 1983 movie ''Joysticks'' and in the 1983 movie ''Koyaanisqatsi - Life out of Balance''.

MB (Milton Bradley) released a boardgame based on this video game (same name) in 1983 : Win the most points by using your Defender ships to protect Humanoids from waves of aliens. A set of chance cards will bring the different aliens (bombers, landers and Humanoids) into play. Movement is determined with a spinner. Players can move their defenders and aliens.

- UPDATES -

Defender ROM sets were distinguished by early and later editions. The early edition supported only upright cabinets. In 1981 Williams released a cocktail cabinet version which necessitated extra code to flip the video display and to support a second set of game controls. The editions had some minor differences in the game's attract mode : The early edition gave an erroneous point value of '100' for alien landers; this was corrected to '150' in the later edition. Also, the high score value for player PGD was '14185' in the early edition and '14285' in the later edition.

Early edition ROM sets :
* Defender (White Label)
* Defender (Green Label)

Later edition ROM sets :
* Defender (Red Label)

- SCORING -

Lander : 150 points
Mutant : 150 points
Baiter : 200 points
Bomber : 250 points
Pod : 1000 points
Swarmer : 150 points

Saving a human from a Lander : 500 points
Depositing a human into the ground : 500 points
Human landing into the ground safely on his own : 250 points

Bonus at the end of each wave :
Wave 1 : Humans Left X 100.
Wave 2 : Humans Left X 200.
Wave 3 : Humans Left X 300.
Wave 4 : Humans Left X 400.
Wave 5 and above : Humans Left X 500.

- TIPS AND TRICKS -

* Avoid using hyperspace unless you are about to die. Fighting off attacks, regardless of the number of enemies will make you a better Defender player.

* Baiters can usually be overcome by hitting the reverse button twice quickly. They will fly past you and be in range for your fire power. Do NOT try to outrun them as Baiters are faster than your ship.

* Swarmers are easy to defeat. You can hit reverse as soon as they fly past you and fly behind them. They cannot shoot backwards so you can blast away at will.

* At higher levels, you will need to play God and even sacrifice some humanoids (by killing them yourself) to preserve the rest of the planet's population. The planet is too large for you protect and you are sparing the humanoids from a fate worst than death (mutation). Do not worry, these humanoids reproduce quickly and overpopulation has always been a constant problem. The planet will be fully populated at the start of every fifth attack wave (configurable).

* See Credits : To see the designers credits, do the following while in game play : Down, Reverse, 1P Start, Thrust, Reverse, 2P Start, Fire, Down, 1P Start, Thrust and Fire.

* The International Date Line : There are reverse lines for swarmers and mutants (aka the 'International Date Line'). If this line is between you and the type of enemy in question, they will travel the opposite direction around the planet to get you (I.e. they won't cross this line to get to you). If a mutant, say, is following you and you cross the mutant reverse line (to the left of the Big Mountain) it will suddenly reverse direction and go around the other way. The same is true for the swarmer reverse line (located approximately where your ship starts each wave). This doesn't affect swarmers that you are following behind. If you're on one side of the line and a pod is on the other and you shoot it open the swarmers will fly away from you and you can get in behind them immediately. The best use of these lines is where there are lots of swarmers and/or mutants that you don't want to hassle with. You stay near the line in question and go back and forth over it to keep the enemy in question on the other side of the planet. Especially useful in space and waves that get really hairy.

* Freeze!! : You can freeze a Defender machine by picking up all ten humans (on any wave, but Wave 1 is your greatest chance at success), stopping all forward motion of your ship, quieting the screen down (i.e. having no enemies moving around on it) and setting all the humans straight down quickly. This seems to work better were the terrain is very close to the bottom of the screen. Every thing will freeze, but you can still move your ship up and down. Thrusting will break the spell, so to speak. If you do pick a spot with shallow terrain, some humans will go thru the bottom of the screen and appear suspended in mid-air near the top. This trick is good during marathon games when you've reached Wave 256 and need a breather.

* Some top players begin each round by shooting their own men, except for one, which they pick up. This keeps mutants from developing, but it also means that the world explodes if you lose your last humanoid. It probably goes without saying that this can be considered an 'advanced' trick...

* When you get your last official guy before 1, 000, 000, every time you score, you'll get an extra man. The trick we used was to win 100+ ships between 990, 000 and 1, 000, 000, thus fooling the game based on where score rolls over rather than where ships roll over. The version where you win 100+ ships has been tested, the version where you win 256+ ships never was because :
a) For every point scored in Defender from 990, 000 to 999, 975 you will win one extra ship and smart bomb.
b) If you suicide on something, including a shot but not including hyperspace (because dying from hyperspace awards no points), you will lose one ship, but also gain one (net effect on ships is zero) plus one smart bomb.
c) For winning n ships in Defender from 990, 000 to 999, 975, including suicides, you will have to wait n x 10, 000 points after passing 1M before the game's accounting balances and it awards ships properly at 10, 000 point intervals again. d. The score returns to zero every 1 million, meaning that if you had won 100 ships the machine would have to wait 1 million points to begin awarding ships again. However, since 1 million is equivalent to zero it awards them immediately at 1, 010, 000. -- or --
d) Being an 8-bit game, 255 ships is the maximum recognized. 256 ships/smart bombs is treated as zero. If you win exactly 256 ships during this period the machine will think you have won none and thus begin awarding ships immediately at 1, 010, 000.

* In either case, you get to keep your surplus ships and bombs and can have super long turns where you bomb 2 to 3 times per wave to get out of dangerous situations. It's possible on a real Defender machine to make the screen color inverted so that all the black space is white while you are playing. It will reset itself when you die and maybe by hyperspacing. Smartbomb flashes are cool when it's reversed. The trick, as I remember it, was to drop a credit in right when you die and the screen flashes white. Somehow the program gets distracted (non masked interrupt on coin drop?) and it the screen stays white.

* Defender attack waves ''roll over'' at wave 100, which is displayed, after being completed, as wave 0. The game keeps track of the actual number of waves, even though they are not shown properly. For example, the next wave will be counted as wave 101, even though it shows being completed as wave 1. The game will 'roll over' again at wave 200, which is displayed, after being completed, as wave 0 as well.

The next 'roll over' occurs at wave 256. Upon completion of wave 255, the next wave is a 'blank' wave, in which no enemies appear, and the wave immediately ends after the players ship appears on screen. This level is counted and displayed as Wave 0, and the player is awarded a bonus of Humans left X 0 points (The bonus for this wave is always 0 points). The next wave is wave 1, and the game now plays just as if the player had started a new game, except the player gets to keep his score and all of his bonus ships & smart bombs.

- SERIES -

1. Defender (1980)
2. Stargate (1981)
3. Strikeforce (1991)
4. Defender 2000 (1996, Atari Jaguar)

- STAFF -

Staff : Eugene Jarvis (DRJ), Sam Dicker (SAM), Larry DeMar (LED), Paul Dussault (PGD), (CRB), Mike Stroll (MRS), Steve Ritchie (SSR), (TMH)

- PORTS -

* Consoles :
Atari 2600 (1981)
Atari 5200 (1982)
Entex AdventureVision (1982)
Atari XEGS
Colecovision (1983)
Mattel Intellivision (1983)
Nintendo Super Famicom (1996, "Williams Arcade's Greatest Hits")
Sega Mega Drive (1996, "Williams Arcade's Greatest Hits")
Atari Jaguar (1996, "Defender 2000")
Sega Saturn (1996, "Williams Arcade's Greatest Hits")
Sony PlayStation (1996, "Williams Arcade's Greatest Hits")
Nintendo 64 (2000, "Midway's Greatest Arcade Hits Volume I")
Nintendo Game Boy Advance (2002)
Sony PlayStation 2 (2003, "Midway Arcade Treasure")
Nintendo GameCube (2003, "Midway Arcade Treasure")
Microsoft XBOX (2003, "Midway Arcade Treasure")

* Computers :
Atari 800 (1982)
Commodore VIC-20 (1983)
PC [MS-DOS] (1995, "Williams Arcade Classics")
PC [MS Windows] (1996, "Williams Arcade Classics")
PC [MS Windows, CD-ROM] (2004, "Midway Arcade Treasure")
Microtan 65
Apple II

* Others :
VFD handheld game (1982) released by Entex.
VFD handheld game (19??) released by Gakken : The screen is a little smaller than the Entex version.
Palm OS ("Midway Arcade Classic")

 

 

 

 

[jongolo]

Seems to me that a keypad would be a great controller for this...

That would be so neat to have a game that used the Star Raiders keypad - - envisioning a really cool keypad overlay! Maybe the ability to use either different combination presses on the 7800 controller second button or mashing buttons on the keypad.

[Synthpopalooza]

Seems to me the answer is simple:

 

left button - fire ... right button - smart bomb ... hold both buttons - hyperspace.

 

But then what do you do for inviso?

[Jinks]

Seems to me the answer is simple:

 

left button - fire ... right button - smart bomb ... hold both buttons - hyperspace.

 

But then what do you do for inviso?

both buttons? left held then right? hyperspace is right button held

[+Random Terrain]

But then what do you do for inviso?

both buttons? left held then right? hyperspace is right button held

Seems like you guys are making it harder than it needs to be.

 

Example:

 

Fire Button #1:

 

Fire. (Hold for rapid-fire.)

 

 

Fire Button #2:

 

Smart Bomb - Quick press and release of button #2.

 

Hyperspace - Hold button #2 for at least 1 second, then release.

 

Inviso - Double click button #2. [in case it's not obvious, this would only be used in the sequel.]

 

[Assignment order not set in stone. It's only an example. Hopefully the game would let the player select the order.]

[iesposta]

The fact that reading the Keypad takes forever in processor time means it is probably a no-go for a game with lots of things happening on and off screen. Quite unfortunate.

 

So if you can take your hand off a controller to use a keypad, you can use a second controller for more options like 2600 Stargate/Defender II, or have the choice of one controller with options like RT says... or I like the idea of instant hyperspace by mashing both buttons, and is Inviso even in Defender?

[+Random Terrain]

. . . and is Inviso even in Defender?

People started discussing what could be used in the sequel. The holding down both buttons option should probably be avoided since some people might already be holding down the fire button for rapid fire. Better to leave the fire button out of it and have all special abilities involve nothing but the second button.

 

(Players using a PS2 controller or something else that has more than 3 buttons will have a button for every special ability.)

[timdu]

Rybags mentions books on the DP site.

 

All of those and more books are on my web site 2600 Connection now:

 

http://www.2600connection.com/books/books.html

 

 

enjoy!

 

Tim