Trying to bankswitch ... having troubles

[R_Leo_1]

It's very confusing indeed, hope we can get it fixed.

Here's the zip:

LL128KProject.zip

[RevEng]

It's working for me with the altgamestart, for the most part. You haven't included a drawscreen command, and there's no loop, so it the 6502 reaches the empty rom and starts to execute it.

 

Try adding the following to your code after your plotsprite command...

main 
        drawscreen
        goto main

 

[R_Leo_1]

Yes! It worked, I had put the startup.asm in the wrong place. Thanks a million for all the assistance! 

And @mksmith thanks a ton as well for the help

[R_Leo_1]

Welp, apologies for the double-post, but it seems a new problem has made itself known. Although the first bank works just fine, bank 2's "dmahole 0 noflow" is not able to get to my code it seems. Same issue as before, in the other banks. Am I able to use the "altgamestart" in other banks as well, or will there need to be another solution?

[RevEng]

Theres only one place where your game can start. You should be able to use goto to get to any other dmahole.  

 

[edit] with "noflow" it's up to you to goto/gosub in and out of dmaholes. Thing of them as isolated pockets of rom that you can never reach or leave, except via goto/gosub.

[R_Leo_1]

Okay I see, so should the goto be before the dmahole command or after?

[RevEng]

I can't tell you a hard rule for where to place your gotos. It depends on how the code flows, and  more specifically, where you want it to flow.

 

If you're in one dma hole and want to go to the next, then you can do something like...

 dmahole 0 noflow
altgamestart    ; the game logic starts here
 [some game code]
 goto nextcode  ; without this goto, we'd hit the wall of dmahole 1. Instead we need to "goto" a destination somewhere...
 dmahole 1 noflow
nextcode
 [more game code] ; ...where the code flow will continue
 goto someotherplace

 

The point is just to never hit the wall at the start or end of a dmahole. So this is invalid...

 [some game logic code]
 ; bad - missing a goto to get to the code in dmahole 0
 dmahole 0 noflow
 [some more game logic]

As is this...

 goto mycode ; good
 dmahole 0 noflow
mycode
 [some game logic]
 ; bad - missing a goto to get to dma hole 1 code
 dmahole 1 noflow
 [more game logic]

 

If you use "dmahole" without the "noflow" argument, then all of this can be skipped, and code will flow naturally from one hole to the next. But you can't stuff the rom full of graphics that way. When you stuff things to the max, the price you pay is to use "noflow", with the consequence that you need to navigate your code flow in and out of these islands of rom.

[R_Leo_1]

This is perfect, just the explanation I needed. Was able to reach the code in my second bank just fine now

Once again, thanks for the help and apologies for the constant questions ?

[+mksmith]

On 9/24/2020 at 3:40 AM, RevEng said:

If you use "dmahole" without the "noflow" argument, then all of this can be skipped, and code will flow naturally from one hole to the next. But you can't stuff the rom full of graphics that way. When you stuff things to the max, the price you pay is to use "noflow", with the consequence that you need to navigate your code flow in and out of these islands of rom.

Ah interesting to know that Mike!