Working with mondern tools and vintage chip I am looking into the use of AMD's 2900 family of chips. The plans are to extend this knowledge into the design of bit sliced computers.
The first part of this will be to access the functionality of the AM2901 4 bit slice ALU. This 40 pin dip chip contains the ALU section of a CPU. This chips are designed to work together so you can extend the size of the ALU 4 bits at a time. In the documentation notes on setting up 64 bit ALUs. When using multiple slices carry operations can be sped up using AM2902 look a head carry chip. This is the same as what can be done with 74X181 ALUs.
Internally 16 four bit words of dual port ram. This ram is accessed by addressing it through the A and B ports of the chip. A 1 word scratch pad register Q. A one word data in port and a one word output port.
There are Up/Down shift functions avalible for RAM and the Q register. A strange quirk of the shifter is that you can shift the RAM address Or The RAM and the Q register.