Reproduction micros

On 17 July 2016 at 20:54, Peter Corlett <abuse at cabal.org.uk> wrote: Exactly so. This is part of the brilliance of the Archimedes, AIUI. In detailed technical ways I confess I do not fully understand, the ARM2 and its chipset's design was optimised to work with cheap DRAM with relatively slow cycle times. The OS also ran directly from ROM. Even PCs at the time copied their BIOS ROM to RAM for faster execution. Acorn designed around this. Similarly, one of the pleasant features of the Psion 3 & 5 series PDAs was that their OS ran from ROM. Thus, although the OSes were very stable & seldom needed reboots, when they did, it was reasonably quick and the machines were highly functional with, even in the late models, as little as 8-16MB of RAM, running a rich pre-emptive multitasking GUI OS. Compare with, e.g., Android or iOS, where the OS is stored in ROM but can't execute from it. Thus, slow boot times as the entire thing must be *copied* to RAM at IPL. And of course as these run not-very-cut-down 1960s/1970s minicomputer multiuser OSes, the OSes themselves occupy many hundreds of meg, these days edging to gigabyte range. -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)