Hi, I'm planning to have a go at using ethernet with PICs. I thought I would start with the ENC28J60 but eventually I want to move onto 32-bit PICs which have ethernet built in. I've been reading the datasheet for the ENC28J60 but I don't understand the magnetics part. I've been looking at ethernet sockets that have built in magnetics as they are supposed to be simpler but I'm still having a hard time picking the correct one.

I've been looking at these 2. I found this numbering system on another site for the same part. Both parts seem to be 10/100 5core. I tried googling to find out what these cores are but I didn't find anything that made sense. The only thing I can think of is that it references the number of wires that are used.

Is there a page somewhere that explains what all this stuff means in detail or can someone give me some information on it? I know I could get a plugin module to do the job but I want to learn how to do it myself.