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Connect Arduino UNO to a Laser with TCP/IP or RS232 protocol Answered

Hi everyone, I am trying to comunicate with a Laser via ethernet or RS232 but I realy don't find enough information in internet to make my sketch. For TCP/IP, I am using a ENC28J60.

CLK ---> D8

SO ---> D12

SCK --->D13

SI --->D11

CS --->D10

VCC --->3,3v


You will find attached the manual for TCP/IP comunications that the laser company gave me.

Finaly for RS232, I tried to use the TTL-RS232 module (MAX3232) to comunicate but I was not able to make it works. (attached the manual for RS232 comunications that the laser company gave me.

RXD ---> RX 0

TXD ---> TX 1

VCC ---> 5v

GNS ---> GND

Please could somebody helps me with the code.

Thank you,



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2 years ago

For RS232 you probably just need to swap the receive and transmit pins. RS232 protocol states that each device will have a transmit and receive pin. In order to "hear" a device the transmit needs to enter the receive pin of the other device and vice versa.


For ethernet, if the laser has an RJ45 connector like the

ENC28J60 you will need to use a crossover network similar to what you would do with RS232. Transmit needs to enter the Receive pins. The difference here is that there are 4 wires to swap. See the discussion here:


Good Luck!