So I thought I'd give it another go to try the bgfx ntsc monochrome decoding under ubuntu and it just makes the screen go black.

mono screen before enabling ntsc
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getting ready to enable NTSC:
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and screen going to black:
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Am I doing it wrong?

Not a big deal, just gotta try all the features!

BTW it's cool now the //e has a "zipchip 4mhz" machine configuration option 8-) You can really tell when the zipchip is active because the cursor really blinks fast.