2019-07-02 01:05:25 +10:00
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# Sega Master System
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The Sega Master System was a popular gaming console running on z80. It has a
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simple, solid design and, most interestingly of all, its even more popular
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successor, the Megadrive (Genesis) had a z80 system for compatibility!
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This makes this platform *very* scavenge-friendly and worth working on.
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[SMS Power][smspower] is an awesome technical resource to develop for this
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platform and this is where most of my information comes from.
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This platform is tight on RAM. It has 8k of it. However, if you have extra RAM,
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you can put it on your cartridge.
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## Status
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I'm experimenting. Collapse OS doesn't run on the SMS yet. There are two main
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challenges to solve: interfacing a keyboard through its I/O system (should be
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feasible. from what I read in the I/O specs, it's very well done and adaptable)
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and interface with its VDP (Video Display Processor).
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After that, I'll look into using the explansion slot so that I can reuse the
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RC2014 bus to, for example, access SD cards.
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## Usage
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The binary produced by the Makefile here has been tested on a Genesis +
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[Everdrive MD][everdrive] (I haven't built myself a writable cartridge yet).
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It is an adaptation of Maxim's (from SMS power) hello world. I converted it to
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2019-07-02 05:46:10 +10:00
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ZASM. It shows a letter in the range of "a" to "i" depending of which button on
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controller A is pressed (only detects one button at once). All buttons of the
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genesis controller are supported. Shows "i" when no button is pressed.
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2019-07-02 01:05:25 +10:00
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I've also added the mandatory "TMR SEGA" header at the end of the binary.
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[smspower]: http://www.smspower.org
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[everdrive]: https://krikzz.com
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