Is the scan functionality on this machine standalone? By this I mean: can you make scan settings independently of a connected computer and also scan any number of pages in succession and then merge them into a single pdf, either send it by e-mail or save it on a USB stick? I've had multifunctional devices whose internal software/hardware was so inadequate that you could only scan one page at a time and then had to start all over again (even with the settings!). Thank you!