Ethernet and Servo Control

I purchased the Ethernet Starter Kit with RCM3710 about a year ago. It came with Dynamic C Lite V8.51. I have been able to successfully implement basic RC servo control for a robotics application using the Hobbyist.lib servo functions. I have also been able to establish a basic TCP/IP wireless connection / web server to my laptop using the TCP/IP libraries.

Now the fun begins. When I try to use the TCP/IP functions AND the servo functions in the same program, to control the robot, the web server stops working and I cannot ping the RCM3710. I am trying to debug this and here are my initial questions:

  1. I cannot see the source code for the TCP/IP llibraries when I try to open, for example http.lib. The editor window opens, but it is blank. This is case for all of the .lib files in the TCP_IP folder. How can I view the source for .lib files to aid in debugging?

  2. Since I can’t view the source code for the .lib files, does anyone know if the http.lib or dcrtcp.lib uses hardware resources that would conflict with the servo functions? The servo functions use Timer A and B plus some of the PE1, PE4, PE5, and PE7.

Your help is greatly appreciated! :confused:

Problem Fixed! I got help from tech support yesterday. For anyone having a similiar problem, keep in mind that http_handler() must be called often (every 10ms or so…) to keep TCP and web services alive. I had call HBservoInit() before initializing sockets and http. It was apparently taking too long to initialize.


Hi Mooreaw,

I am new to this site, and I saw you did the RC servo application. I bought a demo board RCM2300, and I want to write a program for my RC servo. Could you give me a recommendation to where to start to work with the code? I did a search on the web and understand the basic servo signal, so I want to produce that using RCM2300 demo board. Thanks in advanced.




I am not familiar with the RCM2300. My RCM3700 came with a starter board and lots of sample programs including one for RC servos. I didn’t write it.

Check to see if you have a library file called hobbyist.lib in any of the directories containing library files. Mine was in the top level directory called “libraries” immediately under the DC_Lite directory. If you have this file, it has basic servo control functions built into it. Since you are basically familiar with how an RC servo works, you should have no problem understanding how to use these functions.



I searched for the hobbyist.lib file in the lib folder, and I could not find it. I installed the Dynamic C 8.0, and I downloaded the latest version 8.61. I looked for it again, but I did not find it either.

Yes, I understand the basic signal for RC servo, and I even wrote a small script using VHDL for the Altera chip. However, I am very new to the Rabbit, so I am learning right now. Is there anyway that you can email me that Hobbyist.lib file and your C code to control the RC servo? Many thanks in advanced.