I have a Brother Printer (DCP-L2541DW) which has a flat bed scanner and an ADF. The scanner does not due duplex scanning though. At the moment i am using brscan to enable the 'Scan to PC' on the printer. This way i can scan a document with a press of a button.

As i mentioned the printer can only do single side scanning. After it has scanned the page, the printer LCD does pop a question whether to scan another page or continue. Unfortunately, brscan (using scanimage) does not scan the second page at all. I am curious whether your code can be used with brscan for manual duplex scanning using the flat bed scanner?