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Matmook

[rmw Bit Usage]

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Matmook    1

Hi,

 

Using CRY16 video mode, I'm currently trying to set the RMW bit on one of my sprite but this doesn't have the same behavior in Tempest and on my Jaguar-BJL...

 

Tempest : my sprite disappear when RMW bit is set :huh:

Jaguar-BJL : It works ! :yes:

 

Is there a trick to make this mode running in tempest and Jag-BJL ? :wacko:

 

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Zerosquare    10

When Project Tempest and a real Jaguar don't agree, usually the real Jaguar is right :P

 

Sorry, I don't know if (and how) it is possible to work around PT's behaviour. Personally I don't use emulators at all when developing for the Jaguar : they're not reliable, there are just too many differences between their emulation and the real hardware. The Jaguar is already complicated enough as it is ;)

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Orion_    1

I once used project tempest to develop until the day my source code was running perfectly on project tempest and absolutely not on my jaguar. and I had no idea why and was too far in the code to check where was the bug.

maybe you can try Virtual Jaguar which is far more reliable on jaguar emulation, but still, this is not a good idea, since the jaguar emulators are far from reacting like a real jaguar

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Matmook    1
I once used project tempest to develop until the day my source code was running perfectly on project tempest and absolutely not on my jaguar. and I had no idea why and was too far in the code to check where was the bug.

I've got a sort of bug like this between Tempest and Jaguar.

It was just (for my case) the fact that Tempest's memory is always clear while Jaguar's one is in random state upon startup ...

maybe you can try Virtual Jaguar which is far more reliable on jaguar emulation, but still, this is not a good idea, since the jaguar emulators are far from reacting like a real jaguar

 

I know this is not a good idea but since I don't have a BJL-Portable-Jaguar (Dream...) I must sometime use emulator to develop ..

 

So I've try with Virtual Jaguar and :yes: :yes: :yes:!!

 

So now I need to rebuild VJ to load .bin file instead of .jag

 

Thanks :lol:

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Fadest    0
I've got a sort of bug like this between Tempest and Jaguar.

It was just (for my case) the fact that Tempest's memory is always clear while Jaguar's one is in random state upon startup ...

This is a well known problem on Lynx with a BLL kit.

As a program is loaded into RAM (in order to be able to download program to test), the RAM is not clear of course. So if you don't initialize new variables (which is a really bad idea), you have (randoms) problems... Of course, in Handy, there is no problem as nothing is loaded into RAM before.

I suppose this must be the same with the BJL kit from Protector SE for example...

 

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Zerosquare    10

In fact, the problem is more broad than that. The important thing is, unless the OS/loader program/etc. explicitly sets the RAM to a known value (e.g. the BSS sections in Atari programs are set to zero by the TOS), you should never assume anything about the contents. Even if nothing had been written there before, the contents of RAM chips at power-up are not zero, they are random.

 

(In fact they're not truly random ; there is very often a repeating pattern which depends on the electrical implementation of the RAM cells)

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Matmook    1
In fact, the problem is more broad than that. The important thing is, unless the OS/loader program/etc. explicitly sets the RAM to a known value (e.g. the BSS sections in Atari programs are set to zero by the TOS),

 

That's why loading some prog on my falcon took so much time ... Very Interesting !

 

 

you should never assume anything about the contents. Even if nothing had been written there before, the contents of RAM chips at power-up are not zero, they are random.

 

(In fact they're not truly random ; there is very often a repeating pattern which depends on the electrical implementation of the RAM cells)

 

 

OOps, I've found in another post that Orion_ has allready done the job for Virtual Jaguar's bin file support : Virtual Jaguar Bjl Bin File Support

 

So thanks a lot Orion :yes:

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Matmook    1
Congratulation Mbarreteau ! you write the 10000th post of Jagware :)

 

:yes: :yes:

 

Clap Clap Clap....

 

:D:D:D:D

 

Thanks, Thanks ...I do not expect to win ... :cry: ... sorry ... emotion.

...

I want to thanks my mother, my producer, my keyboard and my cat how have supported me posting on this forum....

...

 

:sweating::D

 

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That's why loading some prog on my falcon took so much time ... Very Interesting !

 

And since TOS 3 (TT, which is the first to have FastRam), there is the FastLoad bit in the GEMDOS program header, which tells the TOS to not zero the BSS section, and leads to fast load times. When you have a 14MB (or more with FastRam) Falcon, program start up time is a bit long without this bit set.

 

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