U1      AT89C2051-20
U2      MAX490 (or comparable)
U3      78L05 / 78S05
X1      16MHz Oszilator
C1,C2   18pF
C3      1uF
C4      1..10uF
C5      100nf
R1      220 Ohm
D1      1N4148
D2      LED
J1      Connector Sub-D 25pin male (printer port)
J2      Connector Sub-D 9pin male (dmx-/power-connector)
