RCM3900 or RCM4300?

Hello,
I�m new in the rabbit world and I need a bit help. In the application I am working I need ADC and the memory features of the 4300 but also I need the modbus libraries. What could be less difficult, making my own libraries of modbus or designing a new pcb with ADC (considering a loose of memory)?

Thank you in advance.

There is a ModBus module that you should be able to use with the RCM4300. Many of the samples were written for our single board computer products, but you should be able to look at the code and get something working far easier than writing your own library. Here is a link to the ModBus library download:

http://www.rabbit.com/support/downloads/modules/modbus.shtml