Code listings for the I4004 or I4040

On Tue, Mar 15, 2016 at 10:54 PM, dwight <dkelvey at hotmail.com> wrote: [...] Unfortunately I do not, but I've recently become interested in such things, as I have received from a friend's estate an old board from an embedded system (possibly a cash register) which has a 4040 CPU. Photos here: https://www.flickr.com/photos/22368471 at N04/sets/72157665878868081/ The board also has the 4008/4009 memory interface, sockets for 16 1702s (I assume, though they are all empty), a bunch of TTL, a bunch of hand-kludged stuff, and two 44-pin .156 pitch edge connectors (on the same edge of the board). It has all of *zero* 4002 RAM chips. Maybe there were 4002 chips on another board. The only marking on the board, on both sides, is "MCS 4/4 N". There are four strange-looking hybrids. Three of the hybrids have 22 pins with 600 mil row pitch, and are labeled (with stylized prefix "IC"): IC6298 751 IC6270 752 IC5220 5002A The fourth hybrid is a six-pin device with 300 mil row pitch, but longer than a 16-pin DIP, and is labelled: IC6302 754 I suspect that the 751, 752, and 754 may be date codes, though the 5002A seems out of place. My guess is that the primary purpose of the hybrids was to make it difficult for competitors to clone the board. For want of information on the board, I'll probably just remove the 4040, 4008, and 4009, and build my own system with them. Would I be correct in thinking that the 4008/4009 (or the later 4289 that replaces them) only serves to interface to program memory, but does not provide means to add RAM in the data address space? (I know that you can put RAM in the program space and write to it with the WPM instruction, but that's nowhere near as convenient to access for data.)