So, what you see here is the complete adress-module of the relay CPU...the first of three plates is now complete:

This module is able to hold a 10 bit program-counter, add +1 if necessary, read/write the program-counter to/from the databus, load a adress from the databus into a adress-register and write the program-counter or the adress-register into an adressbus-register...which is connected to the adressbus.

In the following picture you see the interface: