SIEMENS 100U I/O module problems

I am trying to Re-activate a concrete mixing machine that has a siemens 100U cpu 103 fixed in it. I have the following items , a Siemens programmer PG720, Step 5 ver 7, S5 100U users manual.
The problem I am experiencing is that the CPU cannot "see" the Input and output modules when I perfom a "System Parameters " command.
I am not good in Siemens PLCs because my exposure has been mostly on A-B PLCs.
Can some one tell me how to configure the modules and what software to use. ?
The manuals on the S5 100U products don not show how to.
Please Help me out
Warm Regards
Charles.

I think S5-tool have ever can't show the hw-config.

sepo,
I am lost here,
I don't seem to understand your reply .
rgds
Charles

Dear cmngigi,

I attach S5-100U manual.

If you want to check if a input works
you need to access it with test->Status Varible, but before you must activate online connection on File->Proyect->Adjust->Operation_Mode->On_Line.

Best regards,
Kelkoon