Please post your thread only once. Posting a single thread in the most relevant forum will make it easier for members to help you and will keep the discussion in one place. Your reference to
01000111 where you also posted is a quiet 10 year old thread, so let's allow it to remain that way and continue your discussion here.
If I understand your question, you do not want to carry on any communication over the serial port, instead you only want to toggle the handshaking lines to control an external device...?
In that case, a quick search of LQ threads turns up this C solution,
manually controlling RTS/CTS. You will likely find others using LQ's search function from the right sidebar, and many more including shell based variations using your search engine of choice.
I think that from a shell script you would use
stty to change the state with the device driver. See
man stty for its use, and follow the SEE ALSO links from that page for other serial I/O functions.
Once you have decided on a language and method to toggle the line, it should be easy to wrap it into a loop or function to provide the desired timing delay.
Good luck!
