Comment by functional_dev
9 hours ago
Incredible work! Fitting transformer into 32KB RAM is crazy
For those who read this project and do not know PDP-11 it could be hard to understand that working with these memory limits is difficult. Here is visual guide for PDP11 architecture - https://vectree.io/c/pdp-11-hardware-architecture
Thanks for this amazing project!
That PDP-11 was the most fun minicomputer of the late 1970s in my opinion. Growing up in NH about an hour north of Digital's HQ all sorts of schools from primary to secondary as well as museums had PDP-8, PDP-10, PDP-11 and later VAX machines.
The PDP-11 had a timesharing OS called RSTS/E which could give maybe 10 people a BASIC programming experience a little bit better than an Apple ][. If you were messing with 8-bit microcomputers in 1981 you might think a 16-bit future would look like the PDP-11 but the 1970 design was long in the tooth by 1980 -- like 8-bit micros it was limited to a 64kb logical address space. Virtual memory let it offer 64k environments to more users, but not let a user have a bigger environment.