Hi,
The solution depends on which version of PCS7 you are using, and whether you are using the APL libray or not.
The manuals are available here:
Look for your version of PCS7, then the 'Programming instructions for Blocks', is helpful.
Also the APL Styleguide is essential if its and APL block.
If you are using APL and for the first time, set aside about 3 weeks to generate you blocks in the correct format.
For none APL blocks its less painful, but only just.
I assume you've made your FB and assigned the s7_m_c attribute to the block and the data you want to see.