Twincat, memcpy and type conversion

Hello,

I need to extract some elements for a txt file.
I browse my file using ADR, pointer and have no problem for that.
When I find a element I needm I want to copy it to a variable in the PLC (it could be INT or REAL for example).

My txt file is a long array of bytes within each byte has the ascii code of the correspondant letter.

When I try to get my element, I use the following function:
memcpy(ADR(myVar),ADR(txtElementAdr),ElementLength).
I've no failure but myVar has no sense...

Could you explain me how can I proper get my text element to the typed variable?

Thanks a lot!