moa/todo.txt

* change all the inspection and debugging things to return a struct which can then be printed by the frontend

* there are many issues with the coprocessor address space, and the VDP
* I mapped the sn sound chip into 0xC00010, in the middle of the VDP's address space, and didn't get a runtime error!!! needs fixing
* there should be a better way of aliasing addresses.  Can you make the actual Z80 bus get mapped into 0xA00000?
* turn on warnings about unmapped addresses being accessed

* could have a trait with more housekeeping-type functions, like querying, adding, removing child devices, maybe registering them even
* if you make Bus device just another device, then the coproc bus can be bridged to the main bus of genesis
* the macintosh mainboard has no way of changing the layout if the bus is a generic device (it swaps memory around based on an I/O bit)
* there needs to be a way of doing disparate reads or aliased reads... the sn sound chip being mapped into VDP memory is not the best

* what if, to allow a device to have multiple steppable functions, you pass the system in, or otherwise provide some mechanism for
  each device to create sub devices which are scheduled independently
* should it be possible to reschedule multiple events at different intervals to reduce the times a given step function is called?  Some have
  multiple clocks, or multiple things at different clocks, and making them each an event would mean they could be smaller and faster, but at
  the cost of having more events on the queue when re-scheduling.  There needs to be a mechanism to avoid the event queue ballooning due to
  an error
* can you somehow make devices have two step functions for running things at different times? (I'm thinking ym2612 audio gen vs timers)
* the genesis coprocessor stuff will be a good reference point for things that make multiple devices, and how to add them correctly to the system

* make Signal directional, by making SignalDriver and SignalInput or SignalReceiver

* address repeater on ym2612 doesn't seem to work the same, when it's on the 68000 device.  The Z80 device doesn't have an affect, but maybe it's not being used


* fix the m68k timings
* add rust runtime checks for math to look for overflow errors
* fix the watchers in the Bus, maybe make them manual
* make it possible to compile without audio support (minifb frontend requires it atm)
* does Z80 need a customized Z80BusPort like the 68k?
* can you make it so you don't need borrow_mut() so much?



* make the keys easier to config...

* modify cpal code to skip audio until caught up
* AudioFrame (and possibly the mixer and source) should be moved to the core, it should probably have the sample rate
* split AudioOutput into a sender and receiver
* can you eliminate the source-to-mixer queues?
* add audio support to the console, but it needs to be conditionally compilable so that audio can be disabled (computie doesn't need it, only genesis)
* sound doesn't work on a lot of games... is it a problem with the Z80 accessing the YM2612, or the lack of YM timers? or something else?
* make the ym generate audio in sync so the DAC timings can be more accurate
* add stereo output to ym2612
* you need to scale the output sample to be +/- 1.0 instead of 0-1.0
* fix ym2612 sound generation (no bass, no LFO, etc)


* the interrupt controller stuff is really not good.  It should be more like busport, and connected to a device at startup (eg. create
  interrupt controller, then create objects that use that controller and pass in values, maybe an option so that the controller doesn't
  have to be hooked up, meaning hardware interrupts would not be used.

* should you make Address a newtype and add From impls for each type of numeric, and add utils to wrap address at certain boundaries and such
* should you make a means of storing different kinds of buses?
* should you make buses hide their RcRefCell?


* add doc strings everywhere
* get rustfmt, rustdoc, and clippy working in some kind of semi-automatic fashion

* you really need a full web-based debugger



Web Assembly:

    * can you make the web interface nicer with like... a picture of a genesis or something
    * for some unknown reason, the js-based updater works much better than the rust based one, but the rust based one just goes back to
      a fixed time per loop instead of trying to speed up
    * clean up pixels frontend


System/Traits:

    * maybe I should make ClockDuration use picos as the base instead, and use u64 since that gives like 212 days or something instead of 5h
      and should prevent split nanoseconds which is the main concern

    * add opentelemetry if it can be wasm compatible, or some kind of timing for giving an average framerate
    * can you make the connections between things (like memory adapters), be expressed in a way that's more similar to the electrical design?
      like specifying that address pins 10-7 should be ignored/unconnected, pin 11 will connect to "chip select", etc

    * should you simulate bus arbitration?
    * interrupts could be done in a better way
    * need a better way of handling disparate reads/writes to I/O spaces, rather than having multiple devices or having a massive chunk of address space allocated, continuously
    * should you modify Addressable to also take the absolute address as input?  I'm thinking of how the same device could be mapped to multiple addresses in memory instead
      of taking up a whole range of addresses
    * you could modify read()/write() in Addressable to return the number of bytes read or written for dynamic bus sizing used by the MC68020+

    * add ability to serialize/deserialize state into something, so it can be restored... (maybe not worth it though)


Debugger:

    * the debug dump things should not used the clocked addressing, but use a debugging mode thing of some kind so as not to influence the sim state

    * i need a way to debug only the cpu and not the coprocessor, but that's tricky without a way to id or compare Transmutables
    * add a way to delete a watcher
    * get stack tracing working again, but can you do it with just data?
    * how can you improve the debugger?
    * debugger could maybe even allows arrows left/right for editing, and up/down for history


Genesis/Mega Drive:

    * the 68000/Z80 bank switching is probably buggy
    * the H/V counters are not accurate because it seems to count at different speeds in the blanking period (time vs return value numbers don't divide properly)
    * make the ym7101 set/reset the v_int occurred flag based on the interrupt controller

    * there is an issue with Mortal Kombat 2 where it will crash randomly at the start of a fight.  The code is actually swapping
      stacks a bunch of times, and at some point, the stack is corrupted or something and it `rts`s to the wrong address...

    * add support for the sprite overflow flag (low priority)
    * still possibly a bug with the shadow/highlight colours


Macintosh:

    * issues when booting the rom, attempt to write to rom during the driver init/open phase
    * for the address bus/repeating thing in the mac with the rom and ram, can you make it work for both the 128 and 512


68000:

    * for 68k impl, I want to make some kind of memory transaction object that does everything in a contained but logical way, including handling exception
      information needed about the last access, and adjusting the pre/post inc/dec

    * unimplemented:  BFFFO, BFINS, NBCD, RTD
    * >=MC68020 undecoded & unimplemented: BKPT, CALLM, CAS, CAS2, CHK2, CMP2, RTM, PACK, TRAPcc, UNPK

    * add support for MMU
    * add support for FPU
    * Coprocessor instructions: cpBcc, cpDBcc, cpGEN, cpScc, cpTRAPcc


Z80:

    * unimplemented: CPD, CPDR, CPI, CPIR, DAA, IND, INDR, INI, INIR, INic, INx, OTDR, OTIR, OUTD, OUTI, OUTic, OUTx

Synth:

    * add mouse support to synth app

* can you eventually make the system connections all configurable via a config file?