Working as the CTO at an early stage startup. I've got about 6yrs of dev experience, but was under the impression that under a TN the only matching category was a computer systems analyst, which requires a degree.
CSA does not require a degree. You can use any post secondary diploma and 3 years experience.
If you only have high school, you will have a harder time. You could try tech writer. But if your title is CTO you will have trouble. If you have a certified engineer or scientist as your boss (CEO?) you could be a scientific technician.
Grasmick.com is the lawyer I suggest talking to if you want personal advice. He also has an TN ebook worth buying.