- 16 bit address
- 8 bit data
- can write address to the bus
- can read and write data to the bus
- 56 legal instructions
- each instruction has a size and duration(clock cycles)
- LDA $41 2-BYTE (IMMEDIATE ADDRESSING MODE) [ OPERAND OPCODE ]
- LDA $0105 3-BYTE ( ABSOLUTE ADDRESSING )
- CLC 1-BYTE
For a given instruction we need to implement the function + addressing mode + cycles
- [ 8 BIT ] A (accumulator)
- [ 8 BIT ] X
- [ 8 BIT ] Y
- [ 8 BIT ] stkp STACK POINTER
- [ 16 BIT ] pc PROGRAM COUNTER ( contains the next byte of instruction )
- [ 8 BIT ] status STATUS REGISTER ( check for various operations like carry, enable/disable interrupts and zero compare )
since insrutction can be 1,2 or 3 bytes we might need several clock cycles
- has address and data lines
- 64 kb
Why use unint_x variables Where should we use auto and how What are forward declarations ? and where are they used Circular Dependecy related to forward declarations