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6 Cartridge emulation

The cartridge emulation is another very powerful feature of the

TURBO FREEZER

It is capable of emulating standard 8K and 16K modules as well as bank switching

modules according to the AtariMax/MegaMax and OSS standards. Additionally the new

SpartaDOS X (Ultimate1MB bank switching, up to 512k) can be emulated. Also combined

usage of SpartaDOS X together with an OSS module is allowed.

The cartridge emulation can use all unused memory of the ﬂash ROM (960k) and the

freezer RAM (384K). This means the TURBO FREEZER gives you instant access to up

to 168 diﬀerent modules. The cartridge emulation is not only interesting for those who use

many diﬀerent cartridges and who became tired of changing the cartridges all the time

(which heavily strains the cartridge port), but also for those who develop cartridge based

software. Because the module data can not only be stored in the ﬂash ROM but also in

the freezer RAM, changes to the data can be performed and tested within seconds. Since

the freezer RAM is battery backed its content is not lost after switching the Atari oﬀ. This

means the freezer RAM can be used for storing permanent data, just like the ﬂash ROM.

6.1 Basics

Leveraging the full potential of the cartridge emulation requires knowledge about the

following details of the internal operation.

6.1.1 Bank numbers

The ﬂash ROM is internally divided into “banks” of 8K. With 1MB ﬂash ROM, there are

128 8k banks with the bank numbers 0. . . 127 available. The topmost 64k of the ﬂash

ROM are used by the freezer software and cannot be used for cartridge emulation. This

leaves the banks with the numbers 0. . . 119 for cartridge emulation.

In the 512k freezer RAM the topmost 128k are reserved for the freezer software, leaving

384k in the banks 0. . . 47 for the user. Snapshots are stored in the banks 48. . . 55 of

the freezer RAM. If you don’t use snapshots, you can use these banks also for cartridge

emulation.

16k modules use 2 consecutive 8k banks. Their data must be aligned to a 16k boundary,

i.e. an even bank number. If a 16k module is for example stored in the banks 2 and 3, then

bank 2 will be visible at $8000. . . $9FFF and bank 3 will be visible at $A000. . . $BFFF.

512k modules, SpartaDOS X and modules with

TURBO FREEZER

2005 bank switching

(

8k old

) must be aligned to a 512k boundary. That means they can only start at bank 0

or 64 in the ﬂash ROM or at bank 0 in the freezer RAM.

1 2 ... 36 37 38 39 40 41 42 43 44 45 46 ... 63 64

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Atari 130XE Manual de usuario Pagina 41