So my Lantronix XPort device is now soldered to a breakout board, and I am communicating with it via serial, web, and telnet. My biggest hurdle was getting the XPort to talk to my usb-to-serial board. I had the TX/RX pins flipped. I used my arduino to test it out, and apparently the labelled TX/RX pins become their opposites when the ATMEGA chip is removed. Whodathunkit? Once I figured that out, though, it was relatively smooth sailing. Well, it also took me a while to figure out that Lantronix hardwired the telnet port to be 9999 instead of the standard 23. But then it turned out that this is just the config port, and you CAN change it via the “endpoint configuration” field. So I made it use port 23 after all.
One thing that has come in handy is that Apple has equipped all of their macs with auto-sensing ethernet ports. What this means is that any ethernet cable can be used to connect a mac directly to any ethernet device…no crossover cable is needed. So instead of waiting for ITS to give me an authorized IP address, I created a subnet between my ethernet jack and the XPort so they can talk to one another. The XPort can’t see the internet in this configuration, but it’s fine for initial testing and development. I am going to explore the possibility of using Internet Connection Sharing to make things even easier on me. If the XPort can use my mac’s wireless connection to talk to the internet, I won’t be limited to the few RJ-45 jacks we have here on the floor.