CommanderCoder / JSATOM

JSATOM - Basically JSBEEB with added Acorn Atom + Atommc2
GNU General Public License v3.0
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Remarks working with JSAtom #2

Open oss003 opened 4 years ago

oss003 commented 4 years ago

Hi Andrew,

Just had a play with JSAtom and it looks good ..... nice job.

I do have a few remarks:

- Looks like the vsync signal isn't used in textmode because scrolling and printing text is way to fast
  compared to a real Atom.

- CTRL-G works but beeper sound in games like Chuckie Egg and Galaforce isn't working. 
  Both games are using the VIA timer at #B808/9 for creating sound.

- When you boot in MMC- or in TAPE mode, the diskcontroler area at #0A00 is read only and generates an
  error when written.  This causes a lot of AGD files fail to work.

- There is RAM from #0000-#7FFF (32KB) and from #8000-#9FFF (video RAM), except area #0Axx (Diskcontroller) 

- The AtoMMC is working ok but when you type *CFG C0 the debug mode is entered ......

- The second colourset is not selectable (?#B002=8)

There are also a few options which are available on expanded Atoms like:

- Bankswitching roms at #Axxx through #BFFF

- Joystick emulation, there are 2 'standards': JoyKEY and JoyMMC.
  JoyKEY uses 2 joysticks parallel to the first 2 rows of the keyboard matrix.
  JoyMMC uses PORTB of the AtoMMC to connect a joystick.

- AtomSID

But it's a great emulator written in a short time ....... which is amazing.

PS. I will try a few floppy- and tape images for testing later. I can send you detailed information about the options if you want.

Greetings Kees

CommanderCoder commented 3 years ago

I've made quite a few changes since these issues were raised.

No joystick or ATOM SID yet.