Update specific lines in a file

Hi all,
I want to add a special character ^M to a line, if the line starts with ORDE.
All the other lines should remain unchanged.
Is there sed or other UNIX function who can do this.

Thanx in advance
Auke Quist

not really sure how to use grep but maybe grep for the line with ORDE in it. there is something in man sed that might help its something like [2addr]H Append a newline character followed by the contents of the pattern space to hold the space. I think that could help you maybe? idk just trying to learn by giving suggestions, doing a little research, and seeing if they work

This helps a bit, any other suggestions still welcome

Awk:

/ORDE/ { $0 = $0 "\r" }
{ print }