The Q1 Computer is a project of mine to build a fully functional 8-bit
computer with 16-bit address bus completely out of transistors. Of course,
there is some support circuitry required, most notably, I'm using an SRAM
for the main memory. However, other than the memory, power supply, and LEDs,
all semiconductors are NPN transistors (PN2222A).
Below is a high-level block diagram and a picture of the fully-assembled system. In its current state, the Q1 does not have an X register and the shift and bitwise operators are not yet implemented.
An assembler, simulator, and hardware model for the Q1 are available on GitHub.