[Coco] Cartridges that use SCS decoding

tim lindner tlindner at macmess.org
Thu Mar 9 11:36:59 EST 2017


Ed, you are correct. I mis-typed. It's the SCS signal I am interested in.

I mean to create a list of SCS devices, and non-SCS devices.



On Thu, Mar 9, 2017 at 8:32 AM, Zippster <zippster278 at gmail.com> wrote:
> Hi Tim,
>
> To the best of my knowledge…
>
> *CTS is active only for reads made to the 8K space $C000-$DFFF.  So it
> won’t be used for decoding on any address that requires writes.
>
> You will probably find it is used on every (or nearly every) device that contains an
> on-board ROM.  For instance, it is used as the chip enable signal on the ROM
> chip for the Orchestra 90.
>
> *SCS is active for both reads and writes to $FF40-$FF5F, and will be the main
> arbitration signal for IO (other than ROM reads) when one is used.
>
> Most items (outside of those *CTS ROM reads) don’t use an arbitration signal,
> and do their own decoding in the $FF60-$FF8F range. The RS-232 PAK is one of
> these, according to my info, using $FF68-$FF6B.
>
> - Ed
>
>
>
>
>
>> On Mar 9, 2017, at 8:57 AM, tim lindner <tlindner at macmess.org> wrote:
>>
>> I'd like to get a list of CoCo cartridges that use CTS address
>> decoding, and those that do not.
>>
>> So far I have:
>>
>> Carts that use CTS:
>>  Floppy disk controller
>>
>> Carts that do their own address decoding:
>>  Orch-90
>>  Speech / Sound Cartridge
>>
>> Where does the RS-232 cart fit on this list?
>>
>> What about other carts?
>>
>>
>> --
>> --
>> tim lindner
>>
>> "Proper User Policy apparently means Simon Says."
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco
>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco



-- 
--
tim lindner

"Proper User Policy apparently means Simon Says."


More information about the Coco mailing list