Different result than expected when poking to screen

[emook]

Hello,

In normal basic we can do this following code :

Code:

10 BORDER 0: PAPER 0: INK 6: CLS 20 FOR i=1 TO 7 30 FOR y=0 TO 21 40 FOR x=0 TO 31 50 LET l=22528+x+y*32 60 POKE l,8*i 70 NEXT x 80 NEXT y 90 NEXT i

To fill the screen with the desired colour (I know this example seems pointless, but the same method to poke a screen char is used quite a bit for me)

however, in ZXB it only seems to pokes to the top third of the screen :

Code:

border 0 paper 0 ink 6 cls dim i as ubyte dim x as ubyte dim y as ubyte dim l as uinteger FOR i=1 TO 6 FOR y=0 TO 23 FOR x=0 TO 31 l=22528+x+y*32 POKE l,8*i NEXT NEXT NEXT

Anyone know what I am doing wrong here?

Thanks!