Date: Tue, 8 Jan 2002 15:14:59 -0800 (PST) From: Matthew Dillon <dillon@apollo.backplane.com> To: Terry Lambert <tlambert2@mindspring.com> Cc: D J Hawkey Jr <hawkeyd@visi.com>, freebsd-hackers@FreeBSD.ORG Subject: Re: Oh my god, Google has a USENET archive going back to 1981! Message-ID: <200201082314.g08NExK62190@apollo.backplane.com> References: <20.21dd4868.296bb1c2_aol.com@ns.sol.net> <3C3A810A.C616A903_mindspring.com@ns.sol.net> <200201081104.g08B4i309583@sheol.localdomain> <200201082138.g08LcFS61637@apollo.backplane.com> <3C3B7997.205E404A@mindspring.com>
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:UGH. You didn't load the RAM from the ROM at power on?!?
:
:We had the "high resolution graphics" board in one machine; it's
:where I did my first ray tracing code, for an Optics class. Now
:*that* was a cool third party board, replacing the character
:generator output with bitmapped graphics, and un-overlapping the
:video memory by actually wiring in the chip select for more RAM.
:
:> I had the machine language monitor extension rom.
:
:8-). Quick, what are "A0", "A2", and "A4", and what are their
:operands? What's the difference between "4C" and "6C"? 8-) 8-).
AAaaahhh Aaaahhhhh take them away! take them away! God, it's all
coming back. A2, ldx # immediate.. NO NO! I refuse! The pain, the
pain! My favorite is A1 and B1. NO! STOP!
But, do you know what '02' does? On an original 6502? The 6502
was a hardwired processor, which means that even the hex codes that
didn't have an official instruction did things. Weird things to be
sure, but things nontheless. They cleaned it up later on (in the 816)
but not in the PET/C64 era and not on the 6502 based 65xx series.
Somebody somewhere has a complete list of unsupported instructions
that nevertheless do interesting things.
I wrote a centipede game entirely in machine language and sent it off
to cursor magazine, but they didn't publish it... I think they thought
I might have stolen it or something it was so good :-(. The last level
was the best... the centipede was invisible and only became visible
for a few seconds when you hit it. I *so* wish I still had that code.
:You never did the "Fat Agnes" surgery, or the "Spirit" memory
:board thing on an Amiga 1000, so you could see the "double half
:bright" demo animation of the tap-dancing guy while "In the
:Hall of the Mountain King" played out the speakers?
No, never did that.
:There's also the 68010 hack for the 1000 (you needed to hack
:virus code to make the MPSW fixup patch live across a reboot
:so that you could run the PC and Mac emulators, but it let
:you run SVR3.2 on the A1000, if you had the Supra SCSI drive
:and Zorro controller... ah, the first UNIX box I ever owned...).
:
:-- Terry
Ho!
-Matt
Matthew Dillon
<dillon@backplane.com>
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