Question for Paddle Gurus

[supercat]

Does anyone know the maximum and minimum paddle times that are used by common 2600 games? I know different games use different ranges, without much rhyme or reason. I'm working on a an anti-jitter circuit for 2600 paddles and need to know what timing range I need to implement. In particular, I'm concerned about the low end (short charge time). Also, does anyone know what the threshhold voltage is on the paddle inputs?

[Eckhard Stolberg]

I tried out the paddle range for every known game when I was adding Stelladaptor support to z26. In z26 the paddles are emulated by a counter that flips the corresponding paddle bit in the TIA after a certain number of scanlines. The highest number of scanlines is 260, which is needed for Casino game variation 4. The shortest time is used by Mondo Pong, which starts polling the paddle right after releasing the capacitors. The next game is one of the Party Mix loads, which starts after 2 scanlines.

 

 

Ciao, Eckhard Stolberg

[Rybags]

You might find it easier to do your work on an 800 computer.

 

The paddle scanning is somewhat more automated.

 

There is fast-scan mode which takes 3 scanlines, or normal which can take close to one frame.

 

For some strange reason, the values are 0-227, which corresponds to the number of colour clocks in a scanline.

[supercat]

I tried out the paddle range for every known game when I was adding Stelladaptor support to z26. In z26 the paddles are emulated by a counter that flips the corresponding paddle bit in the TIA after a certain number of scanlines. The highest number of scanlines is 260, which is needed for Casino game variation 4. The shortest time is used by Mondo Pong, which starts polling the paddle right after releasing the capacitors. The next game is one of the Party Mix loads, which starts after 2 scanlines.

 

Hmm... allowing the circuitry to trip the paddles reliably in less than about 15 scan lines could be a little tricky. Not impossible, but complicated by the 1.8K resistor in series with the joyport. Adding a zener to each paddle circuit might ease that problem, but it would be nice to build the board entirely from Radio-Shack available parts. Would the playability of Mondo Pong or Party Mix suffer if the minimum time were 10-15 scan lines?

[Eckhard Stolberg]

Hmm... allowing the circuitry to trip the paddles reliably in less than about 15 scan lines could be a little tricky. Not impossible, but complicated by the 1.8K resistor in series with the joyport. Adding a zener to each paddle circuit might ease that problem, but it would be nice to build the board entirely from Radio-Shack available parts. Would the playability of Mondo Pong or Party Mix suffer if the minimum time were 10-15 scan lines?

Mondo Pong uses a range of 0-100 scanlines for reading the paddle. So you would lose 10-15 %. That would make the game unplayable, since you couldn't hit high balls anymore. For Party Mix I'm not quite sure. IIRC it was the game with the fireball-throwing wizards that needs the quick paddle response. In this game you wouldn't be able to make the wizard's arm move really slowly, which would make aiming more difficult. But the game in general would still be playable.

 

But there are some other games in the 10-15 lines range. Tac Scan for example needs a value of 10 or less for steering sharply to the right. With higher values you'd still be able to turn right, but navigation would much more difficult.

 

 

Ciao, Eckhard Stolberg

[supercat]

But there are some other games in the 10-15 lines range. Tac Scan for example needs a value of 10 or less for steering sharply to the right. With higher values you'd still be able to turn right, but navigation would much more difficult.

 

Hmm.... I may need to add a relaxation oscillator or microcontroller to the thing, then. Bummer--more parts. Any idea about the shortest time games leave the discharge cap enabled?