
Can I use a computer without RAM? - danso
https://www.quora.com/Can-I-use-a-computer-without-a-RAM?share=1
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ggm
I think the narrow answer is, that if the computer has on-chip L1 cache, then
if you can arrange for the L1 cache to contain all the information you need to
run a program, there is no reason in principle why you couldn't run entirely
in L1 cache off the die, and never touch the off-chip memory access channels.

Arranging for state to lie in L1 cache without RAM is a challenge, I wonder if
some combination of things from a JTAG header and chip behaviour could get you
there?

the Boot ROM, in some sense, is the information you minimally are looking at.
So, a boot rom, with state to prep L1 cache and then a run command, which
operates totally in L1 cache?

(I imagine some operations on L1 attempt write-back and would be bad, but
perhaps that can be mitigated by some clever tricks to act like the write-back
worked?)

