1. The number of data buses and the capacity of registers in the Z80 CPU are both 8 bits, so it is an 8-bit CPU.
Microcomputer circuit diagram
2. The pair of Vcc and GND is used to power the IC.
3. One binary is one bit, and 8 bits is one byte.
4. The act of reading and writing memory directly from an external device without going through the CPU is called DMA (Direct Memory Access).
5. 74367 is an IC called a "tri-state bus buffer".
6. In the 7404 circuit diagram symbol, the triangle symbol with a small circle at the end represents an inverter, which inverts the electrical signal input on the left. (i.e. 0 changes to 1, 1 changes to 0) output to the right.
