Starting from 1980, I have worked for ABC Company for more than 28 years.
Means you are still working for ABC, so you cannot say that.
Starting from 1980, I had worked for ABC Company for more than 28 years.
Means you no longer work for that company but the past perfect is used to show anteriority to another event in the past. For example you could say:
I had worked for that company for more than 28 years when I decided to make a move.
I decided to make a move after I had worked for that company for more than 28 years.
As a stand alone sentence and without further context to show anteriority to another event the simple past is the best option:
Starting from 1980, I worked for ABC Company for more than 28 years.
You can also have a chain of events in the past:
Starting from 1980, I worked for ABC Company for more than 28 years. Then I decided to make a move and apply for DEF.
There is a very good answer to the question When is the past perfect exactly needed? on ELL.