Amidar

Mayhem · Post by **Mayhem** » Fri Nov 28, 2008 1:16 pm

You got the PRG file? As stated above, enable blocks 1 and 5 and just drag the PRG into the Vice window to autoload. Works for me (v1.22).

nbla000 · Post by **nbla000** » Fri Nov 28, 2008 3:52 pm

Leeeeee wrote:Bah! I can't get this game to work under Vice. It plays the tune and then stops.

How to play Amidar using the files archived on Zimmer (Used for MegaCart too):
http://www.zimmers.net/anonftp/pub/cbm/ ... Amidar.prg

Though is in the ROM section, the game works in RAM and need 8K on BLK5 ONLY.

How to play it successfully on a real VIC:
- Use a common 8k cbm expansion
- open it and set switch 1 to ON and others to OFF, now 8K are on BLK5
- load Amidar: LOAD "AMIDAR",X,1 (where X is the drive Number)
- reset the vic or type: SYS64802

How to play it successfully on VICE, both 1.22 and 2.0 versions:
-Start Vice
-go to Settings --> VIC settings...
-Click on No expansion memory and after Block 5 and OK
-Drag the PRG into the Vice window to autoload
-after the RUN soft-reset the Vic [ALT+R] or type SYS64802

Using the file present on Zimmer you CANNOT use 8K in BLK1 otherwise after the reset you got a black screen with Amidar writing in the bottom/right

This file version works with Flexicart too, personally tested.

Mayhem wrote:As stated above, enable blocks 1 and 5 and just drag the PRG into the Vice window to autoload. Works for me (v1.22).

If this works you have a different version from Zimmer.
Just for fun, some time ago, i've BLK1 fixed and crunched it but my version requires both BLK1 and BLK5, since it's a really strange VIC configuration i never published my version, you must have another file, may i check ?
May you post your file version ?

Leeeeee · Post by **Leeeeee** » Fri Nov 28, 2008 5:46 pm

Stupid buggy program. Fixed it now so it works with any combination of RAM in blocks 0, 1, 2 and 3

Lee.

Mayhem · Post by **Mayhem** » Fri Nov 28, 2008 6:05 pm

nbla000 wrote:If this works you have a different version from Zimmer.
Just for fun, some time ago, i've BLK1 fixed and crunched it but my version requires both BLK1 and BLK5, since it's a really strange VIC configuration i never published my version, you must have another file, may i check ?
May you post your file version ?

It is a bit funny, took some trial and error to see what blocks it needed. Most bizarre. Anyhow, you can grab the version I'm using here.

Leeeeee · Post by **Leeeeee** » Fri Nov 28, 2008 6:22 pm

Anyhow, you can grab the version I'm using here.

That's a very different version. Not only is it relocated from $A000 to $1201 it has shrunk from 8192 bytes to 3822 bytes. Of course it now needs there to be RAM in BLK1

Lee.

Leeeeee · Post by **Leeeeee** » Fri Nov 28, 2008 8:33 pm

Ok, scratch that. It looks very different because it's packed. The unpacked version is almost identical but has two patches. One to make it work regardless of RAM in BLK1, which is almost the same as the fix I'd worked out, and one to address the PAL/NTSC issues.

Lee.

nbla000 · Post by **nbla000** » Sat Nov 29, 2008 7:38 am

Hey guys, this is my fixed version

I use exactly this version on MegaCart to preserve space and for PAL/NTSC fix, i don't remember when but i've sent it to you obviously

For MegaCart i use VIC+32K configuration.

Leeeeee · Post by **Leeeeee** » Sun Nov 30, 2008 5:24 am

Would someone try this version and let me know how they think it plays compared to the original.

The RAM in BLK1 and PAL/NTSC issues should be fixed.

Whole chunks of redundant code and data have been removed and most of the remaining code re written to make it shorter. The whole thing is about one hundred bytes over the 4K size now but there is still a fair bit of code to look at and other redundant bytes that could be removed.

One result of these changes was that it played much faster so I slowed it down again and now it seems to play slightly slower than the original, though the relative speed of player vs. aliens remains unchanged.

Due to lots of self modifying code this can't be ROMed yet but I'm sure it could be done.

There are some other things that could be done, the score could increment without stopping the gameplay, the characters could be animated etc.

Finally, yes I know it's green. That's so I can tell which one I'm trying to play.

Lee.

Leeeeee · Post by **Leeeeee** » Sun Nov 30, 2008 7:56 am

Updated. Lots shorter and increments the aliens one per level. Also fixes a small bug with the alien movement.

Lee.

nbla000 · Post by **nbla000** » Sun Nov 30, 2008 12:20 pm

I've checked it a bit, i prefer the black screen btw do you think to modify it too or just optimize ?

Leeeeee · Post by **Leeeeee** » Sun Nov 30, 2008 12:42 pm

I prefer the black screen as well, I only made it green so I can tell which is which when I'm running more than one instance of vice. If you want to change it back to black search the file for $A9,$5D and change the $5D to $08.

I was really an exercise in making sense of what was going on, the reduction in size was mostly incidental. One thing I did change was to make the aliens increase one per level up to a maximum of ten instead of going from three on level one to six on level two to ten on all following levels until level 256 where it goes back to three.

If you can think of any play changes to make I could try to include them.

I'm down to 3636 bytes now BTW.

Lee.

nbla000 · Post by **nbla000** » Mon Dec 01, 2008 3:38 am

No, i haven't any ideas...

eslapion · Post by **eslapion** » Mon Dec 01, 2008 7:28 am

@6502dude:

Last year, you were asking what games could pose problems if there was RAM in some areas, apparently, Amidar is one of them.

6502dude · Post by **6502dude** » Mon Dec 01, 2008 8:42 am

eslapion wrote:@6502dude:

Last year, you were asking what games could pose problems if there was RAM in some areas, apparently, Amidar is one of them.

It works fine on MegaCart

Leeeeee · Post by **Leeeeee** » Tue Dec 02, 2008 3:34 pm

This is now a ROMable version of Amidar. The archive contains two files, the .prg file is a normal program file with a prefixed load address and the .rom file is a 4K cart image made by removing the start address and padding the file to 4K.

Both have a green border/background to distinguish then from the original. If you want a black border/background then the byte at $005B in the .rom file, $005D in the .prg file, should be changed to $08.

The final code size is 3219 bytes but this could even be shorter if the screen data was compressed.

Lee.