Q:

Use a receiptprinter in WinRT over serial port

i wanna print to a receipt printer. This would be plugged to a RS323 port. Mostly over a USB adapter. 
The reason is, that I try to implement a small cashier app. So there would it be fantastic if I can print through a receipt printer device.
So my Question is, is it possible to communicate with this device within a windows store app (WinRT)? Or is that not possible in general? 

A:

Serial and parallel ports are not supported in WinRT as can be seen in: MSDN
There is a line in the table describing that there is no WinRT alternative for the serial and parallel port support that existed int the Win32 API.
Best regards

