Apologies for the confusion. What I meant to put over was:

I - refered to the website I got the stepper driver code I am using from (referenced in my first post.

You - said "Your reference to the website incurred me to think you found this code rather than wrote it..."

I - was trying to point out that I HAD found the code rather than created it.

However, I have now found out that no PC software-only scope using the sound card will provide a DC service, so I am no further forward...