On Fri, Jun 1, 2018 at 6:08 PM, Robert Armstrong via cctalk <cctalk@classiccmp.org> wrote: >>Eric Smith <space...@gmail.com> wrote: > >>The control stores of the 11/785, 8600, and 8650 were entirely WCS. >> >>All other VAXen had (relatively) large ROM control store and tiny WCS or >>patch store. > > You forgot the 11/730 and 725. The KA730 used 2901 bit slicers and the > control store was entirely in RAM. After power on it was a paperweight
Indeed. I think others mentioned that processor too.. For some reason the control store was built from 16K DRAMs, and the CPU has to wait while they are refreshed every few milliseconds. > until the 8085 CFE loaded the microcode. Loaded from a TU58 cartridge, which is the main reason my 11/730 is not running at the moment. The hardware is fine, I've rebuilt the drive rollers, but as yet don't have a readable tape (not even blank, to write the microcode onto). Incidentally, did DEC ever release any details (flowcharts, source listings, etc) of the 11/730 microcode? And what about the control PROMs for the memory system. The technical manual implies there was a listing of those, but I've never found it. -tony
