(a) At the close of the evidence or at such earlier time before or during the trial as the court reasonably directs, any party may file written requests that the court instruct the jury on the law as set forth in the requests. At the same time copies of such requests shall be furnished to all parties. Before instructing the jury the court shall conduct a formal instruction conference out of the presence of the jury at which the court shall inform counsel of the proposed action upon their requests and shall afford them an opportunity to offer specific, legal objection to any instruction the court intends to give and to offer alternate instructions. No party may assign as error any portion of the charge or omission therefrom unless that party objects thereto before the jury is instructed, stating distinctly the matter to which the party objects and the grounds of the objection. Before the argument of the case to the jury has begun, the court shall give to the jury such instructions on the law as may be necessary and the same shall be in writing, numbered and signed by the judge, and shall be taken by the jury when it retires. (b) The court shall also provide the jury with appropriate preliminary instructions at the beginning of the trial. Before opening statements, the court shall provide jurors with any general and case-specific instructions that would seem likely to help jurors understand their function during trial, and the issues that they will be required to decide. These preliminary instructions should include any pertinent case-specific instructions that the court anticipates including in the final jury instructions, if the court concludes that it would be helpful to jurors to receive the instructions both at the beginning of the case and again before closing arguments. The court shall confer with counsel at the pretrial conference to determine which instructions should be given to jurors before opening statements. For preliminary instructions, the court shall follow the procedures set forth in subsection (a) with respect to objections and use of written instructions.