RS232 TTL does not send data

I do not know English well and write via google translator. Thank you in advance!
I need to connect arduino to rfid reader. The reader has an output rs232
there are only three wires that are connected to 2, 3, 5 pins.
I bought TTL rs232 for arduino.
connected rs232 to arduino:
VCC - 5v;
RXD - pin10;
TXD - pin11;
There is a special program for rfid rmder.
When you connect the computer and the reader everything works.
connected arduino and reader in this way:

nothing works
Then I connected the arduino to my computer. Data reading works, sending does not work.


#include <SoftwareSerial.h>
SoftwareSerial mySerial(10, 11); // RX, TX

void loop() {
  if(mySerial.available() > 0) {
  if(Serial.available() > 0) {
    mySerial.write(; //or print()

The read function works, the write function does not work.
P.S I wanted to send 3 photos only one

That code doesn't work, the necessary setup() routine got lost somewhere.

What does that exactly mean? Do you receive everything from the reader but you can't send anything? In this case the wiring is wrong. Unfortunately the picture doesn't provide enough information about the wiring.

Poking wires into connectors is doomed to failure too , wire up correctly !

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