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Michael Duffy (mduffy@aludra.usc.edu) wrote:
>: The following code gives me a divide error:
>: 
>:  mov  ax,0035h
>:  mov  dx,01h
>:  div  dx

Yes indeed.  The 80x86 will give you a divide error anytime the quotient is
too large to fit into the destination register.  This code divides the 32-bit
unsigned integer in DX:AX -- namely 010035H -- by the 16-bit unsigned integer
in DX -- namely 0001H -- and is supposed to return the quotient -- 010035H --
in AX (with the remainder in DX).  It won't fit, so a divide exception is
raised.

In article <1992Dec18.094825.14710@miavx1.acs.muohio.edu> sjmadsen@apsvax.aps.muohio.edu (Steve Madsen) writes:
>	You could try changing DX to DL and see if that works.  Since
>you are assigned DX to what looks like a byte value anyway, this might
>solve your problem. 

This will not raise the exception, but it changes the instruction semantics.
It divides the 16-bit unsigned number in AX by the 8-bit number in DL and
returns the quotient in AL and the remainder in AH.  So "div dl" would
function as a no-op with 0035H in AX and 01H in DL.

heard