POKE unexpand ,POKE 32k ???

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CBMBSW
Vic 20 Newbie
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Location: w.germany
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POKE unexpand ,POKE 32k ???

Post by CBMBSW »

hi out there, i have an emergent question.
if i chance the colors in an unexpanded vic with POKE 36879,X
and i try this on 32k expanded vic is it the same or are there differences ???
and if there are, how can i calculate it for my basic program

thanks 4 help

:shock:
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Mike
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Re: POKE unexpand ,POKE 32k ???

Post by Mike »

Put the question the other way round: why do you think there could be any differences in the behaviour or location of that register between unexpanded and 32K expanded VIC-20s?

That notwithstanding the obvious suggestion to just try it out, on real h/w or in VICE.
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vicist
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Re: POKE unexpand ,POKE 32k ???

Post by vicist »

36879 changes the border/foreground colours and is unaffected by additional ram.

I think you're getting this confused with screen colour memory which moves when ram is added.
unexpanded = 38400 - 38905
8k+ expanded = 37888 - 38393

So, poke 38400,2 would make the top left character red on an unexpanded Vic and poke 37888,2 does the same thing on a Vic with 8k or more of added ram. The difference is 512.
CBMBSW
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Joined: Fri Feb 19, 2016 2:17 pm
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Re: POKE unexpand ,POKE 32k ???

Post by CBMBSW »

thanks for fast answering too a noob since 1982...the fault was the computer i build it on with a vice emulation...
now ELIZA2016 works fine as prefered. thanks n regards. 8)
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