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Register Transfer Design

This work is mostly an on-paper process and the real first steps toward designing the CPU. Each of the different addressing modes are sketched out and the registers they will require. It became clear that their was a need for two separate temporary 8bit registers (named MBL and MBH, or Memory Buffer Low/High). This was mostly due to the fact that addresses in the CPU are 16 bits which need to be loaded in before the value is placed on the address lines. This processes is significant since it truly gets the designer and strong understanding of the different instructions and what the datapath has to do.

Ian A. Buck
Wed May 20 12:50:42 EDT 1998