Collecting, repairing and preserving vintage machines since 1998.
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"The king of old weird stuff" - Fuzzweed.co.uk, Nov '25
Binary Dinosaurs
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All set up at @computinghistory.org.uk, ‘live’ debugging of the Positron 9000.
What witchcraft is this?! A long lost prototype? a re-imagined Dragon for the 21st century? Well, I'm not going to tell you. All I can say is that it's not mine (although I WANT IT) and you'll have to come to the Dragon Meetup on SUNDAY to find out - www.computinghistory.org.uk/det/76704/Dr...
Binary Dinosaurs
HereBeDragons
45 year old dust here, probably. Seems a shame to remove this wrap because of all the historic filth.
Aaaand I’ve discovered that the reason (or one of them) it doesn’t boot is the stack is either corrupt or isn’t being written to, so it does an LBSR call and can’t return because the stack contains 0xFFFF instead of 0xF18A. So it could be that nothing is asserting /WR for the RAM.
I feel that I should point out that I’m not actually in that top right pic, I’m out of shot on the right tending to my ‘dragon clones’
*runs away very quickly* 😆
8085 CPUs eh. Bonkers aren't they. I've got a couple here that can't count and go '1, 5, 7, 3, 5 ,5' when tasked with reading NOPs from an EEPROM.
Given the scarcity of literally ANYTHING for the CPT range of word processors I was amazed to be pointed at a sale for some NOS 8" floppies in the proprietary 'word processing' format for my CPT8520.
I might finally be able to make a blank disk image for my machine 🎉 (I know that sounds weird)
Heh. All the labels have fallen off, but the disks seem to be mould free which is all that I need.
That top right picture is *mumbles* years old and I didn't have a grey beard then. Now I do so come see that AND both Positron 9000-based monsters. I'm also bringing my HP1660A logic analyser so I can probe the depths of one or possibly both of them over the course of the weekend 😁
