HI All... Some speed trials:
1) Very early demo version of lemmings... Tested with 40 lemmings onscreen. Average speeds: Normal sam: 15 frames per update 6MHz accelerated: 13 Frames per update 8Mhz accelerated: 11 Frames per update 2) Prince of Persia Normal (ie not the upside-down level) gameplay Average speeds: Normal sam: 4 frames or so per update 8Mhz accelerated: 1 frame per update (and unplayable because of it! :) ) 3) Border scrollers Tend to on average take about 1/2 the time to run... block size still a minimum of 16 pixels, with the possibility of an offset of 8 pixels (ie no change there), but all the delays are screwed up, so it takes up 1/2 the screen size. 4) Basic programs Lots nicer on the whole... Basically, see it at the show... and remember: the release version should run at 18Mhz (if you go for the cheapo one). Interesting facts found out during development: 1) NMOS Z80's output 0 when you do ED 71 (the undocumented OUT (C),0 instruction) 2) CMOS Z80's output &FF when you do the same... good way of determining what type you're using? 3) Z380's ... well... that'd be telling... 4) The ASIC seems to be able to manage asynchronous IOs perfectly well... which is surprising to say the least. Byee! Simon
