Reproducing old machines with newer technology (Re: PDP-12 at the RICM)

On 07/15/2015 01:30 PM, ben wrote: Well, even in the late 70s, 64KB was still a goodly chunk of memory in the microprocessor world. Which reminds me... To bore you with another STAR tale--the machine had two page sizes--the "small" page, which was 512K 64-bit words and the "large page", which was 64K words. What some smart-alec discovered was that in a 512Kw system, it was possible (easily) to write an instruction that could never get started. You could have up to 6 addresses in a vector instruction (3 operands+3 control vectors). Storage was managed in 512 bit "super words". Start your large-page job, put two of the operands near the end of a page and bingo--you get 8 page references just to get the instruction started. Of course, the solution was to sell the customer more memory... --Chuck