jeroen wilbers wrote:

this code looks apealing to me but my assembler caanot cope with
pop dph
pop dpl

Maybe time for a change of assembler?
DPH and DPL are High and Low parts of DPTR, they maybe are not predefined in your assembler, if so you can define them yourself.

dseg at 30h
speed: ds 1
cseg

Means that speed is reserved adress in internal memory (dseg, data segment) at 30H and takes up 1 byte indicated by ds 1 and that the rest is placed in Code segment (cseg)

Anders