This LAN tester circuit originally designed by Vassilis Stergiopoulos. This LAN tester circuit optionally has two designs. The first design is built based 2 main ICs that are timer IC555 and decade counter 4017. The second design is based microcontroller chip ATtiny2313 (the other kind of microcontroller should be work). The first design circuit (555 and 4017) doesn’t need programming, you can use the circuit immediately after assembling. While for the second design, you need to download the program to the microcontroller.
You may download the tutorial of RJ45 LAN tester building include the schematic diagram, circuit explanation, project preview and program source code from the following link:
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