I have a small problem with a with a little serial project I'm working on. I'm trying to send serial commands from an Arduino to a device which accepts a serial connection with a DB25 port. The program that controls this device (a video switcher) puts out a string of hex characters over the serial port to control it. I've captured the hex string and programmed it into the Arduino. The Arduino spits it back out over RS232 fine (under serial monitor it looks identical to the string output when I monitor the serial output of the program).
I have a Wulfden TTL to RS232 converter, which I assume works, although I haven't been able to test it under any other circumstance. I built a DB9 to DB25 cable using only the 4 wires that the converter outputs (TX, RX, Ground, and DTR). The cable works fine between a PC and the switcher, but I am having trouble sending with the Arduino.
I've tried hooking the TX and RX pins on the TTL to RS232 converter to pins 2 and 3 on the Arduino (using software serial) and to 0 and 1 using hardware serial, both polarities. I had the converter's 5V and GND hooked up, but I wasn't sure what to do with RTS pin, so I tried both 5V and GND. I also tried running straight out of pins 0 and 1 without the converter. Assuming the output is correct and the converter works, is there anything else I could be missing? Do I need to do anything in the code to initiate a connection, or do anything with the DTR?
Any help greatly appreciated! Thank you