False Starts



1 bit ALU and shift registers

Until the summer of 2016 this was designed with a 1 bit ALU.  The advantage is a much lower transistor count.   I thought a full adder would be about 20 transistors per register bit, so the full ALU maybe 40 transistors per register bit.   With (say) 8 registers at 4 transistors per register bit the ALU would be significant.   But now  I think the ALU is much smaller than the registers, so may as well build a full ALU.