IM 2

[na_th_an]

Ok, I'm testing some stuff and I've noticed that:

1.- Using the aplib depacker makes subsequent PRINTs to print the text BOLD. A simple Print Bold 0; At y, x; "o"; At cy, cx; " "; solves this issue.

2.- When I fiddle with paging (i.e. run this code)

Code:

Sub mt64x32ShowBuffers ()
    Asm
        di
        ld  a, 5
        ld  bc, $7ffd
        out (c), a
        ld  hl, mt64x32_buffer
        ld  de, $d800
        ld  bc, 512
        ldir
        ld  a, 7
        ld  bc, $7ffd
        out (c), a
        ld  hl, mt64x32_buffer + 512
        ld  de, $d800
        ld  bc, 512
        ldir
        xor a
        ld  bc, $7ffd
        out (c), a  
        ld  ($5b5c), a
        ei
    End Asm
End Sub

The PRINT output gets completely corrupted, as shown in the previous screenshot. So it's not the IM2 code, it's a joint effort between aplib and paging stuff :lol:

The SUB above just pages in RAM 5 to write to screen 0, then pages in RAM 7 to write to screen 1, then pages in RAM 0 so everything is back to normal. How could that mess the PRINT routine so badly?

EDIT: Not just paging, but writing any value to port $7ffd messes up everything (for example, showing screen 1 writing a 1 to bit 3 also messes up things).