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Recipes contain bits and pieces of hardware-related knowledge, but these bits feel sparse. I've been wanting to consolidate hardware- related documentation for a while, but always fell at odds with the recipes organisation. We don't have recipes anymore, just a /doc/hw section that contains hardware-related documentation which often translate to precise instructions to run Collapse OS on a specific machine. With this new organisation, I hope to end up with a better, more solid documentation.
13 lines
491 B
Plaintext
13 lines
491 B
Plaintext
: _zero ( x -- send 0 _data x times )
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( x ) 0 DO 0 _data LOOP ;
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( Each row in ~FNT is a row of the glyph and there is 7 of
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them. We insert a blank one at the end of those 7. For each
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row we set, we need to send 3 zero-bytes because each pixel in
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the tile is actually 4 bits because it can select among 16
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palettes. We use only 2 of them, which is why those bytes
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always stay zero. )
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: _sfont ( a -- Send font to VDP )
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7 0 DO C@+ _data 3 _zero LOOP DROP
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( blank row ) 4 _zero ;
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