Subject: Re: Slightly Off-Topic...
To: NetBSD/alpha Discussion List <firstname.lastname@example.org>
From: Kevin P. Neal <email@example.com>
Date: 06/25/2001 20:03:39
On Mon, Jun 25, 2001 at 11:33:03PM +0200, Michael Kukat wrote:
> On Mon, 25 Jun 2001, Dave McGuire wrote:
> > Good lord, the 6502? I actually like to have some REGISTERS in my
> > processors, thank you. ;)
> Hey, i really like this low-cost RISC chip. This is where i learned assembly
> language on my C16 and later the C64 (remember the Power Music Editor and the
> Deluxe Intro Creator? and some scene stuff on C64). This CPU has a quite nice
> performance, measured to it's age, it is really simple to program (this is
> because it just doesn't know about much :), and you really learn how to handle
> a very reduced set of registers (can we call 2 registers + accumulator a set?)
Uh, to nit pick, the C64 had a 6510 chip, not a 6502. The 6510 had a onboard
8-bit I/O bus that showed up at 0x0000 and 0x0001. Each bit in 0x0000
controlled which direction that line would go. Reads and writes went to
0x0001. The C64 wired it up for memory management. I don't remember what
the C16 did, that was a much much later box. I never quite figured out
what the point of the C16 was.
I loved my C64. It was an awesome box to start out on. Imagine reading in
a manual about how the processor "saw" this and the video chip "saw"
only a fourth of the memory except for the character rom which overlaid
the memory. Except the "color memory" was 4 bits wide and appeared in
memory way up high (0xd000 or thereabouts?).
It's all well and good to read about how this "sees" this and that "sees"
that but nothing beats turning on hi-res graphics mode and seeing on
the screen the low 8k of memory go. See, there's the cassette buffer, and
we can load a program from tape and it shows up there. Oh Oh, and there's
the stack. BASIC memory is there, we load a program from disk and it appears
there. And if we change the location that marks the top of BASIC memory
we can see variables appear onscreen at the very bottom (programs start
towards the top) of the screen.
Awesome. The very basic concepts of modern computing all in flashing
colors and moving pixels on a TV screen. Incredible.
So, I was an Amiga guy. Now I'm an Alpha guy. Uh, what next? Are there
any AT/ATX MIPS boards commonly available kinda cheap here in the US?
Mmmm. Well. Anyway. *shucks*
Kevin P. Neal http://www.pobox.com/~kpn/
Seen on bottom of IBM part number 1887724:
DO NOT EXPOSE MOUSE PAD TO DIRECT SUNLIGHT FOR EXTENDED PERIODS OF TIME.