Your Onkyo DR90 DVD Receiver remote control does not have universal remote functions, and cannot be (easily) programmed to control a Panasonic DMR ES15. Your DR90 remote does have a limited learning function, but it is designed to learn the codes from your TV's remote to control the TV. Only the following buttons are programmable by the TV Learning function:
I hope that helps.
______________________________________________Onkyo DR90 DVD Receiver User Manual Download.