Assembly question

[slenkar]

this is fun

here is how I printed a block to co-ords 7,3

Code:

function FASTCALL drawthis() as ubyte
asm
LD HL,16384
LD BC,7

LD A,3
RRC A
RRC A
RRC A
OR 7
LD L,A

drawblokes:
INC H
LD A,254
LD (HL),A
DEC BC
LD A, B  
OR C    
JP NZ,drawblokes
    end asm
end function

drawthis()
Print "done"

but if I move INC H to just before the jump command the screen goes a bit weird

Code:

function FASTCALL drawthis() as ubyte
asm
LD HL,16384
LD BC,7

LD A,3
RRC A
RRC A
RRC A
OR 7
LD L,A

drawblokes:

LD A,254
LD (HL),A

DEC BC
LD A, B  
OR C
INC H
JP NZ,drawblokes
    end asm
end function

drawthis()
Print "done"

EDIT
ohhh
INC seems to set the zero flag