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Any tips, tricks or tools for Mateos flash cart?


Gemintronic
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  • 2 weeks later...

Froggie.bin is awesome.

If you name it Froggie.32K it uses the TIA sound.

If you name the same file Froggie.32P (and have the Pokey chip in the cart) it plays the Pokey sound!

 

Maybe the same for BeefDrop.bin? I haven't tested that yet.

Edited by iesposta
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Std 7800 banking schemes do not support 144K + Pokey. Usually Pokey is mapped from 16384 to 32767, at that same 16K segment std schemes can have either Pokey, or 8k/16k RAM, or nothing or Page 6 of a 128K ROM bank or 16K extra ROM.
The extra ROM setup is what allows for 144K games, 128K + extra 16K.

I do not know how DK7800 and BB expect to be mapped, even the std scheme with nothing mapped at 16384-32767 would theoretically allow for up to 4MB + Pokey (the 256 pages could all be mapped from 32768 to 49152) but chose to only decode 3 bits (8 pages -> 128K). The Commando PCB supported 5bits decoding (for 512K or 32 pages) but afaik no one used it ... ultimately with a full decoder all 256 pages are accessible if one wants (4MB) in 16K chunks.
More complex schemes could be devised in which Pokey only map at one fixed 16 bytes range in the 16384 to 32767 range and allow the rest to be either ROM or RAM .... but I am not sure anyone attempted it (also you need to write the game explicitly like that)


As I said as I do not know the details of the banking for DK7800/BB maybe they never were made public or simply that cart has not implemented the scheme at all or the documentation is wrong and you need a different extension.

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Std 7800 banking schemes do not support 144K + Pokey. Usually Pokey is mapped from 16384 to 32767, at that same 16K segment std schemes can have either Pokey, or 8k/16k RAM, or nothing or Page 6 of a 128K ROM bank or 16K extra ROM.

The extra ROM setup is what allows for 144K games, 128K + extra 16K.

 

I do not know how DK7800 and BB expect to be mapped, even the std scheme with nothing mapped at 16384-32767 would theoretically allow for up to 4MB + Pokey (the 256 pages could all be mapped from 32768 to 49152) but chose to only decode 3 bits (8 pages -> 128K). The Commando PCB supported 5bits decoding (for 512K or 32 pages) but afaik no one used it ... ultimately with a full decoder all 256 pages are accessible if one wants (4MB) in 16K chunks.

More complex schemes could be devised in which Pokey only map at one fixed 16 bytes range in the 16384 to 32767 range and allow the rest to be either ROM or RAM .... but I am not sure anyone attempted it (also you need to write the game explicitly like that)

 

 

As I said as I do not know the details of the banking for DK7800/BB maybe they never were made public or simply that cart has not implemented the scheme at all or the documentation is wrong and you need a different extension.

 

Details are in the publicly available MAME source code; specifically helpful is this area of the source: \src\devices\bus\a7800\

 

Excerpt:

"...Carts with SuperGame bankswitch 9banks:

9 x 16K banks mappable in 0x8000-0xbfff
bank 7 is always mapped in 0xc000-0xffff
GAMES: Alien Brigade & Crossbow + some homebrew
like Donkey Kong XM demo, Bentley Bear's Crystal
Quest..."
The 'Commando' assignment of POKEY @$4000 is being utilized for RAM, so POKEY is @$0450 instead; denoted in the aforementioned source. This is managed on real hardware by a Versaboard PCB [1st PCB on the left in the aforementioned link] with POKEY chip present; XBoard or XM module can serve as POKEY substitute if none is found on the cart PCB.
Additional excerpt:
"...MegaCart+ = up to 512K (31 banks at $8000, 1 at $C000) of ROM and 2 x 16K RAM @ $4000
VersaBoard = up to 256K of ROM and 2 x 16K RAM
Plus, for the moment, a VersaBoard with POKEY mapped at 0x0450 and support for 144K ROM,
since a few demo homebrew programs seems to use this to combine compatibility with
XBoarD & XM expansions
Note that the VersaBoard can be configured to work with different banking hardware
e.g. with SG 9bank games or with SG + RAM..."
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