Re: [f-cpu] Erin64

[Ben Franchuk <bfranchuk@jetnet.ab.ca>]

richard hartny wrote:
Having used a PDP-8 one finds that is another single primary register
computer. 5 registers - PC,AC,MAR,MDR,IR. With core memory several times
slower than internal operations and needing a write back cycle, it made
more sense to have a read/modify/write architecture than a load/store
one that is used today. Many early machines had the option of index
registers as slow core, or high speed registers.
I think you are right that with routing delays growing compared with
transistor switching speed shrinking, the old architecture's will make a
come back.  
-- 
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
*************************************************************
To unsubscribe, send an e-mail to majordomo@seul.org with
unsubscribe f-cpu       in the body. http://f-cpu.seul.org/