Acorn Atom Emulator

discussion of games, software, hardware & emulators relating to the Acorn Atom
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Re: Acorn Atom Emulator

Post by flohofwoe » Mon Feb 13, 2017 7:29 pm

Thanks for the clarification!

I have implemented the AtoMMC status register (only 'STATUS_OK') and Jet Set Willy is working now in AtoMMC joystick mode. I also added support for keyboard joystick (when testing you'll have to switch on 'joystick mode' by clicking the "JOY" button in the right button row so it turns green. The cursor keys and space will then act as joystick directions and fire button, but this also means that space and cursor as keyboard inputs are disabled, might be a bit confusing...

What's still missing:
- interrupts from the VIA
- a way to load your own TAP files by dropping them into the emulator canvas
- info/about text with Atom history bits and a bit of usage info (especially how to load files)
- I need to figure out a way to get the shift key as separate key into the emulator, some games use this as jump button...

After that I think I'll declare the Atom emulation as 'feature complete', at least for now :)

I haven't added full AtoMMC support though, just the bits that are necessary for joystick input.

Btw, are there any 'must-support' utility ROMs? One thing I might add later is switching ROMs (this would also be a good time for full AtoMMC support). Are there things like programming languages in utility ROMs (Forth, or a standalone assembler maybe?).


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Re: Acorn Atom Emulator

Post by oss003 » Mon Feb 13, 2017 9:00 pm

Hi Floh,

nice job ..... =D>

I think it is easier to implement drag and drop for .ATM files instead of .TAP files.
The ATM file can be loaded direct in the Atom memory at the addresses defined in the header.

The SHIFT and CTRL keys are defined at different addresses compared to the keyboard matrix.
The standard readkey routine at #FE71 only reads the first key pressed and that's why SHIFT and CTRL are used to have the ability to press 2 keys at the same time.

The most used ROM is P-Charme, a utility rom which expands Basic with Procedures and Functions like the BBC.
It also has a 1200 baud cassette reading routine and a Hexdump.

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