Re: [stella] What is at $029c and $029d?

Subject: Re: [stella] What is at $029c and $029d?
From: emooney@xxxxxxxxxxxxxxxx (Erik Mooney)
Date: Thu, 21 Jan 1999 15:55:04 GMT
>Dan was nice enough to send me a partly commented copy of the disassembled
>SC-BIOS. Currently I'm trying to find out what the rest of the code does,
>but there is something I don't understand. In the SC-BIOS there are read
>accesses to $029c and read and write accesses to $029d. $029c seems to
>work similar to INTIM, but I have no idea what $029d is for. Are they
>undocumented RIOT ports or would it be possible, that the SC maps some
>of its ports there? Does anyone have an idea?

Going by the way we understand the 2600's memory architecture, those
addresses would seem to simply get you RAM locations $9c and $9d (but
they'd take an extar cycle to address because they're not zero page.)
The RIOT does not decode address lines 8 through 11.

I think. :)

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