Date: Wed, 9 Jan 2002 11:20:48 +0000 (GMT) From: Doug Rabson <dfr@nlsystems.com> To: Matthew Dillon <dillon@apollo.backplane.com> Cc: <hackers@FreeBSD.ORG> Subject: Re: Oh my god, Google has a USENET archive going back to 1981! Message-ID: <Pine.BSF.4.33.0201091114400.98901-100000@herring.nlsystems.com> In-Reply-To: <200201081932.g08JWNF60649@apollo.backplane.com>
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On Tue, 8 Jan 2002, Matthew Dillon wrote: > : > :That brings back memories. We wrote our own firmware for the 1541 since > :the commodore DOS was so slow. I forget what transfer rate we managed but > :it was much better than the standard code. Bit of a sod to debug though. > : > :-- > :Doug Rabson Mail: dfr@nlsystems.com > : Phone: +44 20 8348 6160 > > Yup. Remember Bryce's 1541 Flash? He was working on beefing up > the C64 serial link while I was working on beefing up the PET's > (software driven) IEEE-488 link. We both managed to increase disk > bandwidth by an order of magnitude, mainly by synchronizing the > computer's 6502 with the peripheral's 65xx and then just stuffing > data into the ports without bothering with any handshakes until the > very end. That old usenet posting I posted has some references to it. I wasn't really into the C64 scene (it cost significant money just to get Usenet access in the UK in those days). I was working on a C64 game at the time and I remember spending many unhappy hours trying to fix some problems with the drive firmware. That was a pretty cool project actually. The game was a text adventure originally written in 68k assembler and we wrote a 68k emulator and VM system which paged the game's 128k address space from the floppy into the C64's teaspoonful of memory. All the development was done on a Microvax running 4.2BSD. The vax generated C64 disk images which we downloaded via the C64's serial port. Those were the days <sigh>. -- Doug Rabson Mail: dfr@nlsystems.com Phone: +44 20 8348 6160 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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