EuroTwo CPU

Latest information are listed here.

  • Holes for signals: 2_2mm vias or pads
  • Holes for currents: 3.2
  • GND on top holes
  • +5V on bottom holes
  • 2x FullAdder / 4x HalfAdder
  • 4x Controlled Inverter from 4Bit Relay Adder
  • 9 Bit AND
  • 4 Bit Register
  • MUX 1-4,1-16, DEC 1-4,1-16, 4 Bit MUX 1-4
  • Clock
  • RAM
  • ROM
  • Logo

This board is made of 120 LEDs just for this board. It is the projectlogo with through-pcb illumination.


  • left


Designator Package Quantity Designation
D* LED_1206_3216 120 blue at 16mA, 5V
R* R_0603_1608 120 330R
C1,C2 CP_Elec_6.3×5.4 2 47uF
C3,C4,C5 C_0805_2012 3 100nF


Testing worked fine. Design looks nice.


I designed a testing board with a SN754410 H-Bridge driver for testing. I can test 4 outputs and 4 inputs per testing board easily with an Arduino now. The SN754410 is still in delivery and will get assembled later.


My automated long term test is up and running. 1000 test-iterations per bit. Tuned the loading speed of the C (adding 100 Ohms), added diodes (1N4007) and tuned the holding voltage of the relais better by adding 100 Ohms.


Fixed the „4-Bit Register rev2“ board. The board is fully functional but has some drawbacks. You need to scratch away 8 traces on the board and solder 8 short wires on it.

The fixes for rev3 are:

  • Cs were not aligned correctly to matching relais. Nobody will see this but still, it is not as intended! Fixed in rev3
  • There is a mistake at the store relays. That is why you need to scratch traces. Fixed in rev3
  • Rev2 is unable to select between rising and falling edge. This is fixed in rev3 by a jumper
  • B.Mask is under the LED-Indicator on the back, that is why the light is not as bright as intended. Fixed in rev3.
  • Numbering of the LEDs would be helpful. Fixed in rev3.


The PCBs for the 4Bit Register and the Logo did arrive. I assembled them successfully. I'm now waiting for the new Relays HK19F for the final test of the registers. In the Logo-PCB there was a little mistake but I succeed fixing it by scraping away two traces.

  • projekte/eurotwo.txt
  • Zuletzt geändert: 2020/10/18 14:26
  • von max