[jloughry]

> a pair of very fast dacs hooked up to the 16 address lines of my computer and another dac hooked up to the databus.

Here's an article about it, with photos [1]. I remember reading it in BYTE, years ago.

https://archive.org/stream/byte-magazine-1978-02/1978_02_BYT...

Edit: I'll bet it's no longer possible to do this on modern CPUs; either the memory busses are inaccessible (SoC) or so highly optimised (DDR4) that it's infeasible to probe them without disrupting the transmission line.

[1] Ciarcia, S. "A Penny Pinching Address State Analyzer". BYTE 3(2), pp. 6--12. February, 1978.

[jerryr]

Bunnie Huang used an FPGA on a pretty fast bus to extract the XBox's ROM. Granted, that's no longer a "modern" CPU, but still interesting.

See the "Update on ROM extraction and decryption" section here: http://www.xenatera.com/bunnie/proj/anatak/xboxmod.html

More info here: http://www.xenatera.com/bunnie/proj/anatak/AIM-2002-008.pdf

And in his book: http://www.nostarch.com/xboxfree

[jacquesm]

Besides that you'd have a serious problem getting a DAC that is fast enough and with enough bits.