Is bank switching enabled by default with intybasic builds and if so, is there a way to explicitly disable it when compiling?

[8bitwidgets.com]

Hi everyone, I have a game from @Brian's Man Cave that i'm having issues getting to work on backbit.  I've talked with @evietron about it and the word i'm hearing is that bank switching is enabled with intybasic by default. 

 

Since Brian's game doesn't use it, I wondered if perhaps the fact that its enabled could be causing an issue with it working on backbit.  This could be a good insight into future rom compatibility issues.

 

The backbit can work with bank switching games via a BIN2ECS she created that converts a .bin into a .ecs file..  which will allow some JLP enabled games and bank switching games (like the bad apple demo) to work on the backbit.  

 

So the steps I took were perfect.rom using rom2bin..  then taking the bin and running it through the bin2ecs..  then tested the ecs file on the backbit it has the same result as just using the original .rom on the backbit as seen in the video below. 

 

 

I'm trying to come up with some consistent symptoms if there are any that might typically cause homebrew games to not work with the backbit that are easily mitigated.  

 

Thanks,

Caleb

[+nanochess]

IntyBASIC doesn't have any kind of bank-switching integrated, in order to not depend on any cartridge PCB or Flash cartridge.

 

However, when you use certain features in IntyBASIC like the extra AY-3-8910 available on the ECS, it adds a small code at $4800 instructing the Intellivision to disable the ECS ROMs.

 

This code simply access the ECS memories and pages out the ECS memory using the ECS bank-switching, so it isn't banking, and it can work with any cartridge PCB.

 

Of course, it is important to notice that the ECS is the one handling the banking of its own ECS memories, and any other hardware should ignore these commands.

 

[8bitwidgets.com]

1 hour ago, nanochess said:

IntyBASIC doesn't have any kind of bank-switching integrated

ah good to know.  thank you for confirming that.  

 

1 hour ago, nanochess said:

when you use certain features in IntyBASIC like the extra AY-3-8910 available on the ECS

I would imagine this is an advanced feature not likely enabled by someone making a basic game?  @Brian's Man Cave you wouldn't have implemented this in your game right?  

 

 

I'm just trying to figure out what is going on at the moment the game flatlines as seen in the video above.  something is happening at that moment that the backbit (only device i am able to confirm has this issue) doesn't like.  

[+nanochess]

Just now, Caleb Garner said:

 

I would imagine this is an advanced feature not likely enabled by someone making a basic game?  @Brian's Man Cave you wouldn't have implemented this in your game right?  

 

 

I'm just trying to figure out what is going on at the moment the game flatlines as seen in the video above.  something is happening at that moment that the backbit (only device i am able to confirm has this issue) doesn't like.  

Not really.

 

Probably many big IntyBASIC games use it for compatibility with ECS.

 

The point is: the ECS ROMs are enabled by default, if someone lets the ECS connected to the Intellivision, then any game using the addresses occupied by the ECS wouldn't work! So the ECS compatibility is just that tiny piece of code at $4800 disabling the ECS, so the game can run without the owner disconnecting the ECS.

 

[8bitwidgets.com]

12 minutes ago, nanochess said:

The point is: the ECS ROMs are enabled by default

Is there an easy way for someone to do a compile that disables ECS?  wondering if maybe this is what's tripping up the backbit?  i mean as you see in the video.  the game runs.  it's something that happens at that moment in the game that is done doing its display of all the pieces to the right that the game flatlines..  so it's not a completely incompatible game, just something is tripping up the backbit at that moment. 

[+fdr4prez]

How about if the Backbit firmware get fixed? 

 

Wasn't that the consensus in the other thread that you made? 

[+nanochess]

11 minutes ago, Caleb Garner said:

Is there an easy way for someone to do a compile that disables ECS?  wondering if maybe this is what's tripping up the backbit?  i mean as you see in the video.  the game runs.  it's something that happens at that moment in the game that is done doing its display of all the pieces to the right that the game flatlines..  so it's not a completely incompatible game, just something is tripping up the backbit at that moment. 

I don't know what's going here. But I'm pretty sure it isn't ECS related.

 

[8bitwidgets.com]

that's good to know.  definitely value your input!  I'm sure whatever it is is a tiny issue, but if I can figure it out it will be one more thing to learn that might help identify a wider "gotcha" that is easily solved for other homebrews on backbit.   plenty of them work so it's not like most fail, but it's irksome when a game decides to not work.  

[mr_me]

Can you post the cfg memory map of this rom.  All three ecs rom locations are bankswitched, two are off by default but the rom at $7000 is on and would have to be bankswitched if the cartridge rom wants to use that segment with an ecs plugged in.

[+Lathe26]

Make sure you upgrade to BackBit firmware version 1.71 or higher.  Prior to that version, the BackBit wasn't reading all the memory layout info stored in the ROM file.  If that doesn't help, then something else is going on.

[8bitwidgets.com]

Absolutely.  These are the 4 files:

 

1 - the original .rom

2 - the rom2bin .bin

3 - the rom2bin .cfg

4 - the bin2ecs .ecs file (this is the one created by the converter made by @evietron specifically for the backbit to interpret for some special features like bank switching and even some jlp stuff

 

 

@Lathe26 I am running 1.72 atm

 

 

perfection.zip

Edited February 5, 2023 by Caleb Garner

[mr_me]

I'll not sure what Evietron might have seen to make her think bankswitching.  Like Nanochess said, it's likely something else.  Does it work on Intellivision hardware with a different cartridge?  The only thing I can see is possible use of read sensitive areas at $c000.

[8bitwidgets.com]

1 minute ago, mr_me said:

Does it work on Intellivision hardware with a different cartridge?

I actually don't know that part.  I only have the backbit.  I'm not sure if @Brian's Man Cave has an LTO.  I can't help but want to assume he does and has tried it on that one.  

 

2 minutes ago, mr_me said:

I'll not sure what Evietron might have seen to make her think bankswitching.

I'm not sure either about this.  Maybe I misunderstood something.  

[Brian's Man Cave]

28 minutes ago, Caleb Garner said:

I actually don't know that part.  I only have the backbit.  I'm not sure if @Brian's Man Cave has an LTO.  I can't help but want to assume he does and has tried it on that one.  

 

I'm not sure either about this.  Maybe I misunderstood something.  

I do have an LTO Flash Cart... can't remember if I tried my Perfect game on it yet or not

[8bitwidgets.com]

11 minutes ago, Brian's Man Cave said:

can't remember if I tried my Perfect game on it yet or not

 

There I go again assuming things..  =D 

 

 

[8bitwidgets.com]

19 hours ago, fdr4prez said:

How about if the Backbit firmware get fixed?

It has been updated / fixed several times, but clearly not all variants have been identified.  

 

19 hours ago, fdr4prez said:

Wasn't that the consensus in the other thread that you made? 

Not sure which other thread, but yea this is me as a gamer, not a developer or hardware maker, just want to be able to play a game and help others be able to play it as well.  I've reached out to all involved parties to see what could be done to fix this, but I don't have much capacity to fix it myself beyond the tools i have available.  I'm sure the solution is not difficult to fix, I just don't know enough about it to solve it myself and hoping others with more insight and knowledge might have the insight.  I can't help but feel like finding the fix to this will pop up elsewhere in other games that might be a new fix that could help more games work.  

[+fdr4prez]

50 minutes ago, Caleb Garner said:

It has been updated / fixed several times, but clearly not all variants have been identified.  

 

Not sure which other thread, but yea this is me as a gamer, not a developer or hardware maker, just want to be able to play a game and help others be able to play it as well.  I've reached out to all involved parties to see what could be done to fix this, but I don't have much capacity to fix it myself beyond the tools i have available.  I'm sure the solution is not difficult to fix, I just don't know enough about it to solve it myself and hoping others with more insight and knowledge might have the insight.  I can't help but feel like finding the fix to this will pop up elsewhere in other games that might be a new fix that could help more games work.  

Sorry, it wasn't a separate thread, but it was in the Stop Express thread.

 

No disrespect to her and her great product, but Evie is welcome to reach out for help, but it seems that you are doing 99% of the communication.

 

Why are you the middleman when there is a technical issue with the backbit?

 

Maybe she is reaching out to more people that have a deeper knowledge of the hardware than we aren't seeing, but if not, please let her know that she isn't alone in this.  As you've seen there are plenty of people here that can help answer questions.

 

It's understood that you want a functional multicart, but you asking the game developers to change their methods is a bit of a reach.

 

The game developers are not the hardware people (either the console or the carts), so why ask them to change their process when their process works?

[8bitwidgets.com]

1 hour ago, fdr4prez said:

Why are you the middleman when there is a technical issue with the backbit?

 

@evietron probably has a "me" on every platform asking for her help lol..  and my goal is to make the backbit a 1:1 alternative to the Flashback.  or at least 1:0.999 (encryption is doubtful as she's not even explored it on any other supported platforms with backbit).. but JLP added math / ram / save / load would go a long way.. 

 

1 hour ago, fdr4prez said:

It's understood that you want a functional multicart, but you asking the game developers to change their methods is a bit of a reach.

I'm not not so much trying to ask them to change their methods, but if there might be some simple fix that could be done that doesn't require a massive refactoring to get working, I would imagine most developers would be open to this if it means more of the community can enjoy their work.  

 

All of this might be moot when the 300 LTOs sitting somewhere incomplete get finished and released.. but i missed the boat 2 years ago.  and I saw the last batch get announced and I was too low on the list to make the cut..  (see gif above) so when the backbit option opened up I jumped on that baby and seeing it's an active product that shows no signs of just drying up and is only stifled by the chip shortage so many hardware makers are facing, so it seemed like a good product to get behind a "multicart-ivus for the rest of us"     

[+fdr4prez]

I totally understand your situation and motives.

 

I've not gotten a backbit, yet, but i may one day.

 

I play mainly in emulation these days, but I do have the LTO Flash! when needed, so there are no pressing needs for me to get a backbit for Inty. 

 

If I get one, then I would be for using it with the Channel F.  I do have the existing fixed-multicart from e5frog, but you can't add new games.  Not that are many new games being worked on for the Channel F, but there are a few new ones.

 

Unfortunately, none of my Channel F consoles are working, so there is no rush for me to get one right now.  There is another new flash/multi-cart in development for the Channel F, so i'll have options to pick from if i ever get around to fixing one of my consoles.

 

The function of being able to use the same backbit on multiple systems, and just use the needed system adapter, is very nice.  But it is of little benefit for me since it would be dedicated to Channel F.  If the backbit and the other new multicart being currently developed are going to be equal in function, in regards to Channel F, then it will simply boil down to price. And certainly the Channel F doesn't need any fancy functions on its carts, so if the backbit is more expensive, then I don't need to pay extra for a multicart that can be used in other systems if I don't use it in other systems.

 

[8bitwidgets.com]

7 hours ago, fdr4prez said:

but I do have the LTO Flash! when needed, so there are no pressing needs for me to get a backbit for Inty. 

yea i'd be cool with an LTO and maybe repurpose my backbit for my Colecovision as I have a 128-in1 which is OK but amazingly 128 slots simply isn't enough..  the backbit would solve this bottleneck..    but until then the backbit is my portal to original hardware with homebrews.  

 

I'm all about playing on original hardware.  I could do emulation.. heck I have the ultimate PC controller adapter so I could hook my flashback or sears controllers to play with a more authentic feel and I have always wanted to do that when I get back into intybasic.. for testing,

 

When I first got into intybasic it never felt real because i couldn't play my games on my intellivision.. but now i can so i'm working to get my other hobbies in check so i can devote my brain to homebrews..   

 

8 hours ago, fdr4prez said:

If I get one, then I would be for using it with the Channel F. 

Nice I just learned about that one last year.. never heard of it before..  actually looks like a really cool system..  I didn't know the backbit would work with that system..  now i have another reason to consider getting one some day.   The only other hiccup is that I'd hope I could find a composite mod for it..  that might be a bridge too far though. 

 

8 hours ago, fdr4prez said:

But it is of little benefit for me since it would be dedicated to Channel F.

yea i bought my backbit perfectly content to let it be dedicated to the Intellivision, but I definitely want to be able to take advantage of JLP storage features for a game..  saving high scores or even for deeper RPG games down the road, save progress..  

 

[+fdr4prez]

I've never played Coleco - ever - and nothing against it, but I'm not interested in it.  I have it setup on my Ulimate Flashback that I made with a bunch of games, including many freely available homebrew, but I've never played any of the games.

 

Channel F was my first console.  It's amazing what you can do with 3-colors.  The controller is quite unique.

 

I guess I can setup Channel F on my Ultimate FB, then I won't need the new flashcart for that either

[8bitwidgets.com]

3 hours ago, fdr4prez said:

I guess I can setup Channel F on my Ultimate FB

Oh that's cool that it can emulate the CF.  I should check that out at some point. 

 

3 hours ago, fdr4prez said:

I've never played Coleco - ever - and nothing against it, but I'm not interested in it. 

Yea didn't have one as a kid, I was an intellivision kid, but I had a best friend in the second grade who did and later an adam.  So that's my personal nostalgia connection to it. 

[Kiwi]

[mapping]
$0000 - $0AFF = $5000
$0B00 - $24FF = $B000

 

There's a big chuck of data at $B000. Probably set the asm org at c100 to avoid the stic aliasing at C000-C03F. Because reading this address strobes the register(s). If you're using the ECS, then mapping at $E000-$EFFF is not ok.  You have to split that data someplace else.  Here's the Memory Map that is a good guide to which memory address is ok, or not if you wish to use the ECS with this game. 

http://wiki.intellivision.us/index.php/Memory_Map

Edited March 9, 2023 by Kiwi