- 1.- Install Twirl TWAIN Probe
- 2.- Start it and select your scanner from the combobox. Click "4 Souce Open", then "Monitor" so Twirl displays changes in every cap.
- 3.- Make sure "Show device UI" is selected, then click "5 Source Enabled".
- 4.- Change values you want to guess in the custom TWAIN UI, then either close it or do a full scan (depending on the maker/model, changes might be not triggered until you scan).
- 5.- Watch changed caps in the text area, check the possible values for those caps in the caps list.
- 6.- Document discovered information, test in custom program and enjoy!
Thanks to spike from Dosadi for the excelent tool that is Twirl.