Denial

When you did not ask about that detail, it was foreseeable to me that you would run into this issue: next logical step after redefining part of a character set would be redefining the entire character set. Quite right. I already had that thought when I was redefining 64 characters, but I wasn't rea...

VIC202.jpg This is my cockpit view. The tricky part was making sure I had the character color available to make the buttons different colors. I think it turned out well. If you want to redefine 256 characters starting from 5120, you will need to protect 2048 bytes from BASIC access from 5120 onward...

Good evening all. My next bit of trouble is redefining all 256 characters. I have 256 data statements each with 8 values separated by commas. I've checked each one. I think my understanding of what I'm doing is no longer valid. I am trying to figure out how to not have an "out of data" err...

I would like to add that not only the letters A..Z can be redefined, you can build an entire new character set from up to 256 characters. There is also no restriction that the symbols shall somehow relate to the original glyphs - their shape is only relevant while you are working in text mode. Some...

It took a few more weeks of practice and learning, and I think I understand how to explain what I've been up to. I might get some of the wording incorrect and maybe not quite explain a concept clearly or accurately. If I missed something, there is a lot of information in this thread that was used to...

Thanks for all the help. I have successfully drawn a full screen image using 8k+ RAM configuration. Here is the image.
I'll post more later. Just happy that it works.

Good morning. I'm a bit frustrated with the vic-20 at the moment. I am trying to write a program for an 8k+ RAM expanded machine. Similar to my other programs, it is going to draw a picture of a tower reaching for the sky. Before POKEing the characters into their screen positions and then POKEing th...

The upper four bits in VIC register 36869 together with the most sig. bit of 36866 define the position of the screen with 512 byte granularity, which is $1000 for the CPU but $3000 for the VIC chip. When you shift left $3000 by 2 binary digits, you get $C000, and it's only the upper nibble, $C, tha...

Point is: leaving the character set at $1C00 and lowering the BASIC limit locks away the entire expansion RAM. With the screen at $1000, this now leaves even less memory available for the BASIC program than with the unexpanded configuration! This makes another issue that I was having make more sens...

POKE 36869, 207 HOLY COW it worked. I am able to print the image with 35k RAM making only this change. Thank you so much for the help. I'm pretty happy with how this picture turned out. I only know how to PRINT a line in one color of multicolor characters, so to change the character color at all, I...

A second issue is, you have your character set data going into 7176. I'm not sure if you meant that, but by the context of your existing code, I'd expect that to be 7168. As far as I know, this allows me to start character redefinition at the letter A and not at the @. I think it's easier for me to...

My apologies. I didn't think the rest of the program was needed as it's just DATA statements and PRINT commands. Here is it in its entirety. If you type it into your machines, it'll make a pretty little picture of a park with 10 colors! 10 POKE 36869,255 20 POKE 646,9 30 POKE 36879,136 40 POKE 36878...

Good evening. I am learning how to redefine characters and print them on the screen to make "mostly" full screen images. I can do it just fine for the stock system and with the 3k RAM expansion installed. It would seem that the process is not the same when using an 8k or higher RAM expansi...