Re: [stella] Zero-Page Memory Addressing.. (Still a newbie, but getting there.)

Subject: Re: [stella] Zero-Page Memory Addressing.. (Still a newbie, but getting there.)
From: Erik Mooney <erik@xxxxxxxxxx>
Date: Fri, 02 Nov 2001 10:27:03 -0500
11/2/2001 10:13:52 AM, "Joel Park" <joelp@xxxxxxxxxxxxxxxxxx> wrote:

>Thank you for the Answers.   You totally confirmed any assumptions I may
>have had.   It really helps to picture Stella as a whole.
>I've got to say that I'm getting excited about this stuff.
>I'm a Visual Basic Programmer by profession,  it's fantastic to find
>something I can do that is so far from programming Visual Basic.

Heh, Me Too.  I write VB for a living, and Stella is a totally different
experience.  Give me VB or give me assembler; none of this wussy
inbetween stuff like C++. :)

>Thanks again for all your help,  y'all never let me down.

A further note:

>> The second half is the famous 128 byte RAM. As you
>> already found out, it's ranging from $80 - $FF.
>> So all RAM access is actually in the zeropage, which
>> means there's very fast access here. (Any serious C64
>> coder would sell his grandma for 128 Bytes free zeropage
>> RAM, BTW :-))

That RAM is also mirrored (access the same bytes through different
addresses) at $180-$1FF.  When RAM is accessed via the stack
manipulation instructions (PHA/PLA/PHP/PLP/JSR/RET), the
6502 uses the $180-$1FF addresses -- that is, the stack is in
page 1.

Archives (includes files) at
Unsub & more at

Current Thread