Article-I.D.: lll-lcc.8601210510.AA03119
Posted: Tue Jan 21 00:10:33 1986
Date-Received: Thu, 23-Jan-86 08:24:47 EST
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 52

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Re: messages 1219, 1272--
[color=blue]>  [/color]
[color=blue]>  On the subject of bank switching in the supercartridges, does anyone[/color]
[color=blue]>  know the software proceedure for getting the cartridge to swap?[/color]
[color=blue]>  Perhaps writing to a particular address in the cartridge address[/color]
[color=blue]>  space?  [/color]

Below is what OSS says about turning their bank-select ROM cartridges
(BASIC XL, MAC/65, Action) on and off (uncovering RAM) without
confusing the OS. 
	Note that remarks about location 3FAh may not be needed for
other than DOS/XL; it is not mentioned in my OS documentation and
I have not experimented.
	If you are using DOS XL with the option that puts most of DOS
in the address space occupied by the cartridge, then you better
not select out the cartridge and mutilate that RAM!
----------------------------------------------------------------------
	Bruce Langdon  L-472                langdon%lll-lcc@lll-crg.ARPA
	Physics Department                  "langdon#bruce%d"@lll-mfe.ARPA
	Lawrence Livermore National Laboratory       
	Livermore, CA 94550                 (415) 422-5444
UUCP: ..{gymble,ihnp4,seismo}!lll-crg!lll-lcc!langdon
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From OSS bbs (408) 446-3451:

Re: Turning Our Carts ON/OFF (S. Grimm)
9/16/85 12:00:00   size: 772

  Sorry that it took so long Steven, but we've finally compiled the right
way to turn the carts on and off:

To Turn a SuperCartridge OFF:
 1 Close Channel 0
 2 Wait for the LSB of the clock (20) to change value.
 3 Do an SEI
 4 Save $AFFF so that you can restore the cart to its previous state.
 5 STA $D508.  This turns cart off.
 6 Poke $3FA,0 to tell OS that there is no cart.
 7 Poke $6A,$C0 (RAMTOP) to tell OS that more RAM is available.
 8 Do a CLI
 9 Open #0,12,0,"E:"

To Turn a Supercartridge back ON:
 1 Perform steps 1-3 from above.
 2 LDX with value saved in 4 above.
 3 STA $D500,X. This turns cart on.
 4 Poke $3FA,1 to tell OS that there is a cart.
 5 Poke $6A,$A0 to tell OS that less RAM is available.
 6 Perform steps 8-9 from above.
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