... and to put oil on the fire, I am thinking about redoing the 6809 part, and replace it by a 68000 at 10 MHz. Maybe a single board with just enough I/O ports (not PIT 68230 IIRC, but simple octal latches) for the pdp8/e console and RAM plus EPROM on board. But as said: I am *thinking* about it. I probably first start figuring out if rewriting the pdp8/e emulator 6809 code into 68000 assembler, making use of all the registers will give the speed increase to compete with the real pdp8/e. I have my doubts. BTW, I have built mid-1995 a simple 68000 design. I could scan it. 64-pin 68000, 2x2764, 2xTC5565, 6800 plus glue logic *and* address and data bus buffers on a single Eurocard. It was modular, as the bus allowed extra cards for PIA's, RAM, EPROM, etc. The above mentioned new design idea is probably loading the CPU a little, because I don't intend to use buffers. Time is the big enemy here! - Henk, PA8PDP. ________________________________ Van: cctalk-bounces at classiccmp.org namens woodelf Verzonden: wo 16-11-2005 18:18 Aan: On-Topic and Off-Topic Posts Onderwerp: Re: homebrew 'puter project Roger Merchberger wrote: You may be better off splitting it into two cards -- cpu and memory and console. A second board for I/O and a optional third for blinking lights. Don't forget Henk has a 6809 cpu that has great blinking lights. It emulates a pdp 8. http://www.pdp-11.nl/ This message and attachment(s) are intended solely for the use of the addressee and may contain information that is privileged, confidential or otherwise exempt from disclosure under applicable law. If you are not the intended recipient or agent thereof responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately by telephone and with a "reply" message. Thank you for your cooperation.