[net.micro.atari] --- 16/32k Action! cart.

nep.pgelhausen@AMES-VMSB.ARPA (01/11/86)

Someone filled in the blank on my comment about the bank selection
abilities of Action!.  I suggested it might be 32k (there was a 
question mark after that estimate) and Ray supplied the proper 8k
figure.  He added that only 8k is in memory at once.  This might
not be true.  According to the documentation, if used in conjunction
with the DOS-XL (the advancement from OS/A+, also by OSS), there is
the possibility that you can access 4 of the 8k that the Action!
cart seems to occupy, reducing the total occupancy to a minimum
of 4k!  (NOTE: I havn't TRIED this, just reporting the possibility...)

Does anyone know if DOS-XL is really required to do this trick?

			-Richard Hartman
			max.hartman@ames-vmsb
------

long@sask.UUCP (Warren Long) (01/13/86)

> Someone filled in the blank on my comment about the bank selection
> abilities of Action!.  I suggested it might be 32k (there was a 
> question mark after that estimate) and Ray supplied the proper 8k
> figure.  He added that only 8k is in memory at once.  This might
> not be true.  According to the documentation, if used in conjunction
> with the DOS-XL (the advancement from OS/A+, also by OSS), there is
> the possibility that you can access 4 of the 8k that the Action!
> cart seems to occupy, reducing the total occupancy to a minimum
> of 4k!  (NOTE: I havn't TRIED this, just reporting the possibility...)
> 
> Does anyone know if DOS-XL is really required to do this trick?
> 
> 			-Richard Hartman
> 			max.hartman@ames-vmsb
> ------


This is  just off the top of my head....

The ACTION (and BASIC XL) cartridgesare what OSS calls 
'Supercartridges'.  They bank-select different segments of ROM
into the memory map.  I believe they are 16K carts.

The reason that DOS XL (and the new SPARTA DOS) use less memory when
used with a supercartridge is that they load part of DOS.SYS in the
ram that is 'under' the cartridge.  This can only be done with
supercartridges because they contain the hardware necessary to
'switch' themselves out of the memory.

			       Warren Long
			       University of Saskatchewan
			       CANADA

ravi@mcnc.UUCP (01/14/86)

>From: nep.pgelhausen@ames-vmsb.ARPA
>
>not be true.  According to the documentation, if used in conjunction
>with the DOS-XL (the advancement from OS/A+, also by OSS), there is
>the possibility that you can access 4 of the 8k that the Action!
>cart seems to occupy, reducing the total occupancy to a minimum
>of 4k!  (NOTE: I havn't TRIED this, just reporting the possibility...)
>
>Does anyone know if DOS-XL is really required to do this trick?
>
>			-Richard Hartman
>			max.hartman@ames-vmsb

This is one of the nice thigs about using DOS-XL (2.3 or later) with OSS's
Supercartridges (like the ACTION! and MAC/65 carts; these are the cartridges
with bank selects etc.).  The DOS actually comes in two forms, and you're
supposed to install one depending on the setup; one for supercarts without
XL machines (ie. the 400/800s) and the other for XL machines, on which
the DOS moves part of itself into the RAM hidden behind the OS, freeing up
some space.  So, using a supercart with DOS-XL on an XL machine one could 
probably be able to hide the cartridge under 4K only.

-- 
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                                     -ravi
				      {decvax,ucbvax}!mcnc!ravi