interfacing PLC with GUI

Hi
i am new on this site.
would like some ideals on the kind of excutables that happen during pc<-->PLC data transfer for siemens LOGO PLC.

i would also like to know the data type store on the memory flash card for the siemens PLCs.

i am doing a project to interface a LOGO PLC through a JAVA GUI. i shuold be able to select any PLC function block program, edit and send it to the PLC via a GUI.

thanx in advance

Now thats a project! But I don't believe you'll find that information in the public domain. Best to contact Siemens and see if they'll help but I would'nt be surprised if they want you to pay for that information. The 'project' you describe would be a very viable commercial product that would compete with their own.

writing to siemens LOGO PLC

does anyone have an ideal on how i can write to the siemens LOGO PLC.

i know the PL:C can be connected to serial port, but what communucation protocol does it use? is it profbus!

Send to LOGO! to ask status: #55#17#17#AA

#06#01 - LOGO! in START mode
#06#42 - LOGO! in STOP mode

Send to LOGO! to START: #55#18#18#AA
Send to LOGO! to STOP : #55#12#12#AA

Continue?