2-sided (Duplex) printing can be enabled through the /Duplex parameter of the setpagedevice operator (standard PS3 behaviour). The older Canon specific /duplex parameter is not supported.
Boolean: true/false.
Changing any parameter of the page device to a new value causes a sheet eject.
If the pagedevice is changed while on the back side of a duplex sheet, the current sheet will be ejected and printing will continue on the front side of a new sheet. “Changed” means that at least one of the pagedevice parameters has a new value.