You may enter a written plea of not guilty and include bail with your letter and ask for a trial date, if you do this be sure to send your letter verified mail with signature receipt. You may also want to consider doing a trial by written declaration which gives you two bites at the apple in that if you lose your trial by written declaration you can re-open your case within 20 days for a court trial.
The above answer is for general information only and is based on the information you posted. Every case is fact dependent, so to get a thorough analysis of your situation, you will need to consult face to face with an attorney licensed to practice in the jurisdiction where the incident took place. Do not conclusively rely on any information posted online when deciding what to do about your case.
You have to have an arraignment first and plead not guilty to get a trial date. At that time officer is supposed to show up. Get an attorney to deal with this.
You can't. Unless you post the bail amount, you must appear on your arraignment date and request a court trial.
Seth Weinstein, Esq.
Practicing throughout Southern California
This reply should NOT be considered a legal opinion of your case / inquiry. At this time I do not have sufficient factual/legal documentation to give a complete answer to your question and there may be more to the issues you raised then I have set out in my brief reply.