> -----Original Message----- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of tony duell > Sent: 18 September 2015 14:33 > To: General Discussion: On-Topic and Off-Topic Posts > <cctalk@classiccmp.org> > Subject: RE: Self modifying code, lambda calculus - Re: ENIAC programming > > > > > > Are there any computers that do let you put microcode into RAM > > > now-days. > >
Of course not sure if it's a stage further or a stage less, but any way, but for any FPGA implementation of a computer, and there are many about, then the entire system definition is stored in RAM which is loaded at power-on... > > "Now-days"? There are some that do that, some of which are still in > > operational shape. Some VAXen, in particular, have something called > > "writable control store", which is essentially microcode RAM. > > As far as I know, the VAX11/730 (There is one next to me waiting for me to > have time to restore it) has the microcode entirely in RAM. Classic PERQs (3 in > the next room) have their microcode entirely in RAM too (in that case, there > is a microcode boot ROM to load the microcode from disk, but it is switched > out after the microcode is loaded). > > > -tony