[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Recommend some documentation



On Sat, 19 Feb 2011, Payton Byrd wrote:

On Feb 19, 12:53 pm, Steve Nickolas
<lyricalnan...@usotsuki.hoshinet.org> wrote:
On Sat, 19 Feb 2011, Payton Byrd wrote:
I just spent some time googling how to change the screen memory that
the 80-column text display is pointing at and didn't find anything
relevant.  Can anyone recommend a good book or other documentation
relating to the programming of 80-column text mode?

There's only two places it can point: page 1 (0/0400-07FF and 1/0400-07FF)
and page 2 (0/0800-0BFF and 1/0800-0BFF).  I'm not even sure if page 2
works with 80-column mode.

-uso.

What register do you set to switch between the two?


Hit C054 (lda/bit) to enable page 1, C055 to enable page 2. This at least works for the old ][-compatible text and graphics modes; I do not know if it also applies to the //e's modes.

-uso.