RE: [stella] 7800 programs -- potential problems?

Subject: RE: [stella] 7800 programs -- potential problems?
From: Eckhard Stolberg <Eckhard_Stolberg@xxxxxxxxxxxxxxxxxxxxx>
Date: Thu, 20 Jan 2000 16:37:05 +0100
>Would it then be possible to write a game that flips back and forth between 
>7800 and 2600 mode, maintaining state?

That would be very difficult, since the register that controls the
state of the RAM, ROM and graphics chip can be accessed by writing to the
low nibble of all addresses between $00 and $1F. Since that overlaps
with many TIA registers (of which only the sound registers are used
in MARIA mode), you would have to be very carefull that you don't
accidentally change the state of something that your code relies on.
Therefore it's better to choose one setting and lock that in.

Ciao, Eckhard Stolberg

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