# To do

- [ ] Figure out why $00 contains $20

## Research

- [ ] Learn how the C64's PC gets initialized (what is the initial value? how is it set?)
- [ ] Review CHIP-8
    - read about the spec / ISA
    - read these, and add them to the bibliography:
        - Steve Losh: https://stevelosh.com/blog/2016/12/chip8-input/
        - https://tonisagrista.com/blog/2021/chip8-spec/

## Misc

- [ ] Play with JSDoc

## Design

- [ ] Add keypad to memory map
- [ ] [Replace CHP/CFC with FHP/FTG](2023-08-07--dev-notes.md)
- [ ] Add a flag for bank-switching to the ~zero-page

### For consideration

- [ ] Subroutine stack
- [ ] [Extended system (secret bonus operations)](2023-08-07--dev-notes.md)

## Programming

- [ ] Write some more complex test programs
    - [ ] Display (hex) numbers
    - [ ] Greater than

## Run-scripts

- [ ] Change interface to run in non-debug mode by default, and use a flag to select debug mode:
    - `./run-cpu.js foo.asm`
    - `./run-cpu.js --debug foo.asm`
    - `./run-cpu.js -d foo.asm`

## Simulator

- [ ] rewrite to call things 'opcodes' and 'operands'

### Assembler

- [ ] Pad up to 256 bytes
- [ ] Validate labels
- [ ] Return pure machine code when printing to stdout (and not in debug mode)

### CPU

- [ ] Add single-stepping 

### Under-the-hood improvements

- [ ] Do a proper binary version... (or lose the typed arrays?)
- [ ] Extract debugging to its own module