About master/slave mode and the EXT pins.

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About master/slave mode and the EXT pins.
by thomson on 2016-04-12 (#168215)
Hello,I read http://www1.cs.columbia.edu/~sedwards/p ... 1989tv.pdf and found EXT values is in effect
when neither BG nor SPR exists.
Please see my picture.

Wiki says
Quote:
When bit 6 of PPUCTRL is clear (the usual case), the PPU gets the palette index for the background color from the EXT pins.


But I think, "When bit 6 of PPUCTRL is clear (the usual case) and neither BG nor SPR exists" is a correct
sentence ,or my understanding is wrong.

What do you think?
Re: About master/slave mode and the EXT pins.
by lidnariq on 2016-04-12 (#168218)
"the palette index for the background color"
"neither BG nor SPR exists"
are almost equivalent sentiments in the case of the NES PPU.

Note that sprite priority does something funny.
Re: About master/slave mode and the EXT pins.
by thomson on 2016-04-12 (#168223)
Oh,I see. I didn't understand.It's my fault.
I thought background color as background tiles color.

Thanks.