I am not sure that the Denon DVD's have discrete power codes. The one DVD listed in the Pronto discrete section uses the Panasonic DVD code and is presumably manufactured by them. I don't know what codes the 1600 uses, the 1500 uses the Denon DVD codes that AFAIK only has a power toggle.

Also, many DVD's turn on from Off with the Play button. If so On=Play/stop and Off=Play/power toggle.

There are a bunch of discrete codes and a conversion utility for pronto codes here:

[Link: remotecentral.com]

-Jon