Search found 5 matches

by shadow
Sat Jan 07, 2017 10:04 pm
Forum: Announcement Board
Topic: Introduce Yourself: What's your User Name based on?
Replies: 659
Views: 345082

Re: Introduce Yourself: What's your User Name based on?

Mike wrote:Not quite. Access of the colour RAM wraps from 38911 ($97FF) to 37888 ($9400) in that case.
Ah, you're absolutely right! I had tried poking the I/O block and knew it didn't work, but somehow it didn't occur to me to check 37888. My mistake!
by shadow
Sat Jan 07, 2017 2:34 am
Forum: Announcement Board
Topic: Introduce Yourself: What's your User Name based on?
Replies: 659
Views: 345082

Re: Introduce Yourself: What's your User Name based on?

Hi there! My username isn't really based upon anything. I needed to make up something, and decided to go with something with a dark theme. (I didn't create it for this site, but rather the C64 wiki, and figured I should stick with it.) I took an interest in 8-bit computers and started poking at the ...
by shadow
Fri Jan 06, 2017 3:53 am
Forum: Programming
Topic: Hello and problem moving screen memory
Replies: 5
Views: 1607

Re: Hello and problem moving screen memory

Just for the sake of it, really. I was thinking of a theoretical cart with RAM in the 3K and 8K positions, and the free memory in one contiguous block. Since the video memory can't be moved above $1E00, contiguous memory meant moving it down.
by shadow
Fri Jan 06, 2017 3:01 am
Forum: Programming
Topic: Hello and problem moving screen memory
Replies: 5
Views: 1607

Re: Hello and problem moving screen memory

Ah, didn't know that, thanks. I was about to add to my post that I couldn't move the character memory there, either, so that explains that. A bit of a missed design opportunity if you ask me- a cart with 3K of RAM at $0400 and 8-24K at $2000 wouldn't have all of the free memory contiguous if the scr...
by shadow
Thu Jan 05, 2017 10:29 pm
Forum: Programming
Topic: Hello and problem moving screen memory
Replies: 5
Views: 1607

Hello and problem moving screen memory

Hello, I've been experimenting with VIC-20 screen POKEs using WinVice. My intent is to move the screen memory into the 3K expansion range, at byte 1024, but I can't make it work. First, having the 3K expansion installed moves the start-of-BASIC address down from 4097 to 1025, so I use this to move i...