Step 5 Query

[woodglass]

I'm trying to program a Step 5 100U PLC (Training myself !).
I'm using Step 5 V7.11 software.

I can create a demo program and transfer it to the PLC, but, if I put the PLC into RUN mode, the RUN LED comes on momentarily, then goes off again (All this time, the STOP LED remains lit).

In the STEP 5 software, if I select [PLC]->[PLC Sys Parameters] from the menu, on screen I get (as well as other info):

I/O module inputs 0
I/O module outputs 0

Any ideas ?.

Thanks in advance

 

[JesperMP]

Dont remember where to find it in STEP5 (it is 10 years since I worked with it regularly).
But try to locate the USTACK and BSTACK. These will tell you why and where the program stopped.
You may have to look into the manual to get further help on the USTACK and BSTACK.