Re: one or two lines scrolling

Spiro Trikaliotis wrote:

> Note, however, that the VIC20 is a little bit different, although the 
> code is almost identical: It can link up to 4 lines together, yielding 
> to a maximum input line length of 4*22=88 characters.

True, but even in that case the link table consists of MSB of the screen 
matrix (i.e. $1E, or $04 on the C64) + $80 for lines not linked so the 
principle to ORA by $80 will break up linked lines on the VIC-20 as well 
as the C64, except here up to 4 physical lines may be linked into one 
logical one.

The 40 column PETs work in a similar manner except the table starts at 
$00E0 instead of $00D9, and the editor doesn't seem to push down text 
when lines are linked? From what emulation tells me, the 80 column PETs 
don't link physical lines at all if you exceed the 80th column, and that 
area at $00E0 seems to have some other use.

No idea about how the Plus/4 line is working, it seems like a different 
universe than the PET/VIC/C64 line.

Best regards

Anders Carlsson