Jump to content
Sign in to follow this  
Nukey Shay

2600 Jr.Pac Speed Throttle

Recommended Posts

Picked at this game a bit...and it's almost working. Hold the button down in-game to move at double speed.

There's still a slight problem due to the way that display scrolling is handled. It's executed apart from the normal movement routine...and then only when it has enough free time to do so. So adding double-speed to the player sprite might cause the display to lag behind a little on occasion (generally when moving Jr. upward...be careful not to let him cross the upper edge of the playfield).

 

 

Test version+assembly:

Jr.PacMan_throttle_.zip

Edited by Nukey Shay

Share this post


Link to post
Share on other sites

Hack corrected.

Instead of doing the whole routine twice to scroll the display...I found that all I needed to do was perform the addition/subtraction to the screen pointers (I'm mistakenly thought that the pointer ram was shared...in which case I wouldn't have been able to do so). Works like a charm now :)

Still mapping out the disassembly file so that more radical additions can be possible (like blue monster point values being shown or adding in a "plus" mode). Current assembly builds seperate NTSC and PAL versions.

Jr.PacMan_throttle_.zip

Share this post


Link to post
Share on other sites

Turbo Pac-Man...this is a cool idea. :D I'm going to try this one out when I get home from work tonight, can't wait!

 

I like the idea of the monster point values being shown...what other ideas do you have brewing for this hack?

 

AM

Share this post


Link to post
Share on other sites

I just played a few rounds. This hack makes this game much more fun for me than the original...it's the first time I've ever cleared the first maze! :D It's pretty hard to turn when you're at the faster speed, I found myself slowing down when I need to make several tight turns in a row. Great Job Nukey, this hack rocks!

 

 

 

AM

Edited by Atarius Maximus

Share this post


Link to post
Share on other sites
I just played a few rounds.  This hack makes this game much more fun for me than the original...it's the first time I've ever cleared the first maze! :D  It's pretty hard to turn when you're at the faster speed, I found myself slowing down when I need to make several tight turns in a row.  Great Job Nukey, this hack rocks!

895441[/snapback]

 

Agreed. Before this, the game was too hard and tedious to be any fun. The hack doesn't exactly makes it easy, but does make it more satisfying. Now if only the monsters would stay blue longer...

Share this post


Link to post
Share on other sites
I just played a few rounds.  This hack makes this game much more fun for me than the original...it's the first time I've ever cleared the first maze! :D  It's pretty hard to turn when you're at the faster speed, I found myself slowing down when I need to make several tight turns in a row.  Great Job Nukey, this hack rocks!

895441[/snapback]

 

Agreed. Before this, the game was too hard and tedious to be any fun. The hack doesn't exactly makes it easy, but does make it more satisfying. Now if only the monsters would stay blue longer...

895451[/snapback]

I dunno - the difficulty makes the game for me. I don't like Ms. Pac-Man (2600) as much because it takes too long to get hard.

 

But if you are going to change other things about Jr. Pac-Man...how about that awful first level color? Yucky.

Share this post


Link to post
Share on other sites
.....I don't like Ms. Pac-Man (2600) as much because it takes too long to get hard....

895735[/snapback]

 

 

Maybe you should try real porn. :ponder:

 

Ok I'm outta here......

 

-Lee

Share this post


Link to post
Share on other sites

I was waiting to see how long it would take for someone to make a comment about that statement :P

Share this post


Link to post
Share on other sites
The speed up chip on the arcade machines makes Pac-Man move at 4x.

896508[/snapback]

 

Yup...that applies to PacMan and Ms. as well (in addition to hacks, etc.). But IMO that's too fast. The existing program can handle up to 3x just by adding an additional byte into the "which object to move?" table...but I think that 2x is just fine :)

Share this post


Link to post
Share on other sites
I just played a few rounds.  This hack makes this game much more fun for me than the original...it's the first time I've ever cleared the first maze! :D  It's pretty hard to turn when you're at the faster speed, I found myself slowing down when I need to make several tight turns in a row.  Great Job Nukey, this hack rocks!

895441[/snapback]

 

Agreed. Before this, the game was too hard and tedious to be any fun. The hack doesn't exactly makes it easy, but does make it more satisfying. Now if only the monsters would stay blue longer...

895451[/snapback]

 

 

That would be simple to do...perhaps add it as a difficulty switch option :)

 

 

 

 

 

I dunno - the difficulty makes the game for me.  I don't like Ms. Pac-Man (2600) as much because it takes too long to get hard.

 

But if you are going to change other things about Jr. Pac-Man...how about that awful first level color?  Yucky.

895735[/snapback]

That's also a good thought...since this hack was basically just trying to retain as much of the original while adding in the new options. I did alter the brightness of the colors a bit already to make a few routines shorter (like the maze flash routine).

Share this post


Link to post
Share on other sites

I like it! When I was going to college (in Northern Oklahoma) a lot of the Pac-Man's and Ms.Pac Man's at the local convenience stores and arcades had that speed chip. Many of them were converted non-successful or older games with bootleg romkits.

 

Could the mazes and Pac Jr. be hacked to make scrolling screen versions of Ms. Pac Man or Pac Man?

Edited by WildBillTX

Share this post


Link to post
Share on other sites

Sure...but since there's no practical way of actually producing a cartridge of superchip games, it would be a lot of work for little gain ;)

Share this post


Link to post
Share on other sites
Sure...but since there's no practical way of actually producing a cartridge of superchip games, it would be a lot of work for little gain ;)

935929[/snapback]

 

 

So is this Jr pac hack a superchip game? As in no cheap 27128 chips allowed? :sad:

Share this post


Link to post
Share on other sites
http://www.tripoint.org/kevtris/files/sizes.txt

 

The hack doesn't change the bankswitching/chip type.  Additional ram is still required for the game to work.

960802[/snapback]

 

Any chance you can make it a non-superchip game? As in not need the extra RAM or is that a pipe dream of mine that is impossible\too much work for what it's worth? :sad: I really like this hack it spices up PACMAN JR and actually makes me what to play it more often but I prefer carts not emulators.

Share this post


Link to post
Share on other sites
Any chance you can make it a non-superchip game? As in not need the extra RAM or is that a pipe dream of mine that is impossible\too much work for what it's worth? :sad:  I really like this hack it spices up PACMAN JR and actually makes me what to play it more often but I prefer carts not emulators.

963018[/snapback]

 

I think there are too many dots. Every eight dots take up a byte of RAM, and the Atari 2600 only has 128 bytes to start with. Add to that the RAM required to track monster positions, perform sprite multiplexing, etc. and there's just no way the 128 bytes of the Atari will be enough.

Share this post


Link to post
Share on other sites
Any chance you can make it a non-superchip game? As in not need the extra RAM or is that a pipe dream of mine that is impossible\too much work for what it's worth? :sad:  I really like this hack it spices up PACMAN JR and actually makes me what to play it more often but I prefer carts not emulators.

963018[/snapback]

 

I think there are too many dots. Every eight dots take up a byte of RAM, and the Atari 2600 only has 128 bytes to start with. Add to that the RAM required to track monster positions, perform sprite multiplexing, etc. and there's just no way the 128 bytes of the Atari will be enough.

963036[/snapback]

 

 

Shitty buzz. But thanks for the info none the less.

Share this post


Link to post
Share on other sites

Note: I think that each dot in Jr. takes 2 bits of ram...since any of them can be large or small.

Share this post


Link to post
Share on other sites
Note: I think that each dot in Jr. takes 2 bits of ram...since any of them can be large or small.

964357[/snapback]

 

I'd neglected to consider that, but it might be interesting to examine the kernel to see. Packing five dots per byte would complicate the kernel slightly (versus using two bits per, or 4 per byte) but probably not unreasonably. It would complicate 'eating' more, but that only needs to be done at most once per frame. Further, things could probably be packed more than that given that the dots are not independent. Indeed, for a group of seven dots in a row, with walls above and below, there are only 239 possible arrangements of dots:

-------   O------   OO-----   OOO----   OOOO---   OOOOO--   OOOOOO-   OOOOOOO
o------   oO-----   oOO----   oOOO---   oOOOO--   oOOOOO-   oOOOOOO   oo-----
ooO----   ooOO---   ooOOO--   ooOOOO-   ooOOOOO   ooo----   oooO---   oooOO--
oooOOO-   oooOOOO   oooo---   ooooO--   ooooOO-   ooooOOO   ooooo--   oooooO-
oooooOO   oooooo-   ooooooO   ooooooo   Oo-----   OoO----   OoOO---   OoOOO--
OoOOOO-   OoOOOOO   Ooo----   OooO---   OooOO--   OooOOO-   OooOOOO   Oooo---
OoooO--   OoooOO-   OoooOOO   Ooooo--   OooooO-   OooooOO   Oooooo-   OoooooO
Ooooooo   OOo----   OOoO---   OOoOO--   OOoOOO-   OOoOOOO   OOoo---   OOooO--
OOooOO-   OOooOOO   OOooo--   OOoooO-   OOoooOO   OOoooo-   OOooooO   OOooooo
OOOo---   OOOoO--   OOOoOO-   OOOoOOO   OOOoo--   OOOooO-   OOOooOO   OOOooo-
OOOoooO   OOOoooo   OOOOo--   OOOOoO-   OOOOoOO   OOOOoo-   OOOOooO   OOOOooo
OOOOOo-   OOOOOoO   OOOOOoo   OOOOOOo   -O-----   -OO----   -OOO---   -OOOO--
-OOOOO-   -OOOOOO   -o-----   -oO----   -oOO---   -oOOO--   -oOOOO-   -oOOOOO
-oo----   -ooO---   -ooOO--   -ooOOO-   -ooOOOO   -ooo---   -oooO--   -oooOO-
-oooOOO   -oooo--   -ooooO-   -ooooOO   -ooooo-   -oooooO   -oooooo   -Oo----
-OoO---   -OoOO--   -OoOOO-   -OoOOOO   -Ooo---   -OooO--   -OooOO-   -OooOOO
-Oooo--   -OoooO-   -OoooOO   -Ooooo-   -OooooO   -Oooooo   -OOo---   -OOoO--
-OOoOO-   -OOoOOO   -OOoo--   -OOooO-   -OOooOO   -OOooo-   -OOoooO   -OOoooo
-OOOo--   -OOOoO-   -OOOoOO   -OOOoo-   -OOOooO   -OOOooo   -OOOOo-   -OOOOoO
-OOOOoo   -OOOOOo   --O----   --OO---   --OOO--   --OOOO-   --OOOOO   --o----
--oO---   --oOO--   --oOOO-   --oOOOO   --oo---   --ooO--   --ooOO-   --ooOOO
--ooo--   --oooO-   --oooOO   --oooo-   --ooooO   --ooooo   --Oo---   --OoO--
--OoOO-   --OoOOO   --Ooo--   --OooO-   --OooOO   --Oooo-   --OoooO   --Ooooo
--OOo--   --OOoO-   --OOoOO   --OOoo-   --OOooO   --OOooo   --OOOo-   --OOOoO
--OOOoo   --OOOOo   ---O---   ---OO--   ---OOO-   ---OOOO   ---o---   ---oO--
---oOO-   ---oOOO   ---oo--   ---ooO-   ---ooOO   ---ooo-   ---oooO   ---oooo
---Oo--   ---OoO-   ---OoOO   ---Ooo-   ---OooO   ---Oooo   ---OOo-   ---OOoO
---OOoo   ---OOOo   ----O--   ----OO-   ----OOO   ----o--   ----oO-   ----oOO
----oo-   ----ooO   ----ooo   ----Oo-   ----OoO   ----Ooo   ----OOo   -----O-
-----OO   -----o-   -----oO   -----oo   -----Oo   ------O   ------o    239

 

I doubt Atari does so, but it would be possible to use lookup tables to unpack such a coding (each byte stores seven dots, at least for certain parts of the maze) on the fly

Share this post


Link to post
Share on other sites

Um...7 bits that can be either on or off yields 128 combinations in just a regular Pac Man game. Jr complicates matters since each bit or dot has 3 frames...large, small, and eaten.

Share this post


Link to post
Share on other sites
Um...7 bits that can be either on or off yields 128 combinations in just a regular Pac Man game.  Jr complicates matters since each bit or dot has 3 frames...large, small, and eaten.

972203[/snapback]

 

Seven dots in a row, without any means of entering or exiting top and bottom, can only exist in one of 29 states:

ooooooo -oooooo --ooooo ---oooo ----ooo -----oo ------o -------
oooooo- -ooooo- --oooo- ---ooo- ----oo- -----o-
ooooo-- -oooo-- --ooo-- ---oo-- ----o--
oooo--- -ooo--- --oo--- ---o---
ooo---- -oo---- --o----
oo----- -o-----
o------

If Pac Man may enter into the middle of a group of dots, then other combinations become possible. But if the only way to eat middle dots is to eat end dots first, then only the combinations above exist.

Share this post


Link to post
Share on other sites

Kinda limits the maze variations a bit...but it still wouldn't matter because the "fruit" object doesn't clear dots as it moves over them, it just makes them larger (and it could begin/end at any point in a row of dots...say if you were killed while it was wandering around).

Share this post


Link to post
Share on other sites

Personaly, I do remember playing and having the Jr. Pac-man for Atari2600. IT was the only decent version of Pac-man for the 2600 in my opinion. If you really wanted to improve the game, they should've made mini movie intermisisons just like the arcade version.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...