Help deciding

Hi guys,

I need some help deciding on what PLC should I use.
It's for controling some pumps and stuff. I've worked several times with PLCs, but now I need to be able to programm and control it through RS232 or RS485 from a java programm. Cost is very important!!
I've been looking into the mitsubishi's FX family an the Simatic S7.

Thanks !!

well i depends on the number of i/o u are using

if it is small u can use an s7-200 + it communication processor

if bigger use s7300 or 400
u must at least specify the number of i/o u need

The number of i/o is not an issue.
What I really need to know is how to program and control the PLC from a java aplication, not from the manufactures app.

Are you wanting to just change the values of certain registers and bits or timers from the java app, or are you wanting to create, edit, and downlaod the ladder program from a java app. The first will be relatively easy, the second will be very difficult.

Thanks!!