add info about GPIB

Author: LilyTronics

readme.md

@@ -23,6 +23,14 @@ Coming up V1.0.0:
 * Data from the table can be copied and pasted to a spreadsheet (Excel, LibreOffice, etc.).
 * Export to CSV for using data in other applications (databases, scripting, etc.).
 
+## About GPIB...
+
+We get some questions if GPIB will be supported. GPIB is a standarized communication bus for instruments. But the standardization is only on the GPIB part.
+The command and response structure are standarized. What is not standarized is the GPIB PC controller. In the past PCs used ISA cards. Now a days you need to have a USB to GPIB controller. And in this controller lies the problem. Supporting the GPIB protocol is fairly easy. Supporting all available GPIB controllers on the market is a headache.
+Every GPIB controller requires its own specific driver. And to test it, we need a sample of each controller available. And those controllers are not cheap.
+So for now it is not very feasible to have GPIB supported. But... if someone is willing to donate a GPIB controller, we will be happy to add support for it.
+
+
 ## Adding your own instruments
 
 You can add your own instruments. A manual for that will be available on the first release.