I am trying to program a PIC16F887 to convert letters into the corresponding morse code and then output it through a speaker. The problem I am having is how to change the frequency of the output.

I'm using assembly/machine language so it's a little rough in terms of trying to get any help with it. I would imagine it would have to be the OSCCON register but I can't seem to figure out how to make it output at 1kHz.

Any help would be greatly appreciated.