Marc wrote... ----- My 1974 HP 21MX, descendant of the HP 2100A, sure inherited this Memory Protect card. One register that you load, prevents access to any memory below the address of the register. ---- That's just the fence register (memory access interception) capability. There's also the I/O & HLT instruction interception, interrupt interception, etc. mentioned earlier.
M.E.M. was standard option (ie. Included) with most E/F machines. I don't know if the 2114/5/6 had the same capabilities in the fence area.... J
