86 replies to this topic

[SIO99]

wesmond, on Fri May 18, 2012 8:57 AM, said:

A bit off topic, but just a starter hint for SIO99 on keypresses, if you haven't got them yet...

10 K=PEEK(764):IF K=255 THEN GOTO 10
20 PRINT K:POKE 764,255:GOTO 10

No, this is wrong! By using PEEKs and POKEs you're descending to the level of the Commodore 64! The way of scanning the keyboard in Atari BASIC isn't by using INKEY$ , but by using GET, as well as a particular syntax involving the use of # and devices which each end in a colon. The listings I read for other BASICs all tried to read keypresses from the keyboard instead of using a joystick, which may not have been supplied with the computer. I think that all Atari computers may have come with a joystick, though. The Atari BASIC editor accepted the statement A$=INKEY$, but it seems that only meant it thought that INKEY$ was a variable. I don't fully understand the command for doing this at the moment, but I'll post it here as soon as I do! The orignal listing I converted even worked on the Sinclair ZX81, so this shows you how crap the Commodore 64 was!

Edited by SIO99, Fri May 18, 2012 5:14 PM.

[Chilly Willy]

Rybags, on Fri May 18, 2012 8:12 AM, said:

Docking is easy, sneak up on the starbase with it near the centre of screen, reduce to 0 velocity once the distance <=4

Don't forget to turn off the shields! You cannot dock while the shields are up. I can't tell you how many times I always forgot that.

[Rybags]

I can't recall having to lower shields - maybe that was changed in a later version.

[Chilly Willy]

Rybags, on Fri May 18, 2012 9:15 PM, said:

I can't recall having to lower shields - maybe that was changed in a later version.

I got the cart (8K) in 82. I was ALWAYS forgetting to turn the damn shields off and the stupid thing wouldn't dock. I even died once because I turned off the shields, started to dock, and got hit by an asteroid.

[SoundGammon]

I really liked the "steering" of your ship in the 5200 version, if you moved the joystick lightly, you would turn slowly, but if you moved it hard, your ship turned harder or faster. That's a plus for those negative controllers!
Wished Activision would have released an updated version of their Skiing game from the 2600 and with a Robotron dual-controller holder and that would have been great!

[ZylonBane]

SIO99, on Fri May 18, 2012 4:58 PM, said:

No, this is wrong! By using PEEKs and POKEs you're descending to the level of the Commodore 64! The way of scanning the keyboard in Atari BASIC isn't by using INKEY$ , but by using GET, as well as a particular syntax involving the use of # and devices which each end in a colon. The listings I read for other BASICs all tried to read keypresses from the keyboard instead of using a joystick, which may not have been supplied with the computer. I think that all Atari computers may have come with a joystick, though. The Atari BASIC editor accepted the statement A$=INKEY$, but it seems that only meant it thought that INKEY$ was a variable. I don't fully understand the command for doing this at the moment, but I'll post it here as soon as I do! The orignal listing I converted even worked on the Sinclair ZX81, so this shows you how crap the Commodore 64 was!

Don't drink and post.

[Rybags]

Shields on docking works fine, even in higher levels.

[Chilly Willy]

Rybags, on Fri May 18, 2012 11:07 PM, said:

Shields on docking works fine, even in higher levels.

Very strange... I'm pretty sure I'm not crazy and turned shields off for no reason.

[wesmond]

To SIO99...

(1) Steady! PEEKs and POKEs are part of the job on pretty much all computers like ours, otherwise you can't get to the "special" things they do. Without it, you won't get any of Atari's goodies - player-missile graphics, redefined characters, or for this example, keyboard scanning. It's just the way it is; Atari BASIC doesn't do these things. "Mapping the Atari" is the book that I reckon most of us will have heard of, if not read, that describes how the Atari is mapped out, and what memory addresses serve which purposes.

(2) The syntax you're talking about is this:

10 OPEN #1,4,0,"K:":GET #1,K

K is then the ASCII value of the you pressed, whereas in the earlier case, K is a keyboard scan code. But this doesn't "scan" for a keypress, it stops what BASIC is doing and waits until you press one. If that's what you want then great, but that's not called scanning the keyboard, it's more like "demanding" a keypress. There isn't a way in Atari Basic to "scan" the keyboard using the IO channels; the way to do that is my earlier example.

We should really relocate or start up a more programming-oriented thread if you like to keep topic etiquette. Very happy to help, but, er, please relax a bit!

W.

Edited by wesmond, Sat May 19, 2012 12:49 AM.

[Almost Rice]

Chilly Willy, on Fri May 18, 2012 11:34 PM, said:

Very strange... I'm pretty sure I'm not crazy and turned shields off for no reason.

Not no reason lowers power usage

[Rybags]

It's a valid strategy to maximize your rank. Even turning off the computer helps.

I don't think asteroids will even appear if the station is onscreen.
3 players for the station at biggest size + 2 torpedos = all PMGs in use.

[Chilly Willy]

Rybags, on Sat May 19, 2012 10:23 AM, said:

It's a valid strategy to maximize your rank. Even turning off the computer helps.

Maybe that's what it was. I remember even turning off the computer after starting a hyperspace jump to save power. If you turned it off too soon after starting, you'd miss your target. It took some experimenting to get the timing right.

Quote

I don't think asteroids will even appear if the station is onscreen.
3 players for the station at biggest size + 2 torpedos = all PMGs in use.

It was before it was larger than one player.