For developers wanting to explore FCM (full-colour mode), it can be quite a daunting journey initially, so here’s some pointers along with an ‘experimentation’ walkthrough that will let you peek and poke your way to a better understanding of FCM

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• I need to divide this by 64 bytes ($40) to get the char index
  (since each pixel within the 8x8 character needs one byte in FCM mode)

  • I.e., $4,0000 / $40 = $1000

• So you need to set:

  • Screen RAM byte 0 to $00

  • Screen RAM byte 1 to $10

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What’s all this about 16-bit character numbers?!

I feel another tripping point that causes initial confusion is the term used for the bitfield “CHR16”:

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The docs for CHR16 say it enables "16-bit character numbers", when in reality, it enables “12-bit character numbers”.

Whether it's worth changing at this stage, I'd lean towards yes, it ought to change to reflect the reality and not mislead, but maybe others might feel the name is locked in now that it has gone to print 😄

Then again, the mega65-book didn't go to print yet, just the user-guide, so maybe there's hope.

FCM Experimentation via the UART monitor

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