If you have a financial calculator such as a Texas Instruments BA series or Hewlett Packard financial calculator, you could set it up to calculate based on a single payment per year.  What you would want to do is set the payments per year to 1.  The remaining settings would be the same as needed for any other mortgage calculation.  Your user manual should cover this scenario in detail.

You need to contact your servicer in order to determine if they are able and/or willing to set up this type of payment arrangement for you.  Your closing documents would spell out the terms and conditions of your payment agreement and this type of payment arrangement is not very common. 

May I ask where you are living?  This type of financing is often available to those who make their living in the agricultural or ranching industry.  Being that these people receive a windfalls due to the harvesting of crops or the processing of livestock many banking institutions will make allowances for this type of payments. 

If you are trying to so this as a means to make your payments due to annual windfall you might want to look at a program that will allow you to make interest only payments during the year and then apply an annual payment to principal.  Typically these payments, as long as they are not greater than 20% are allowed BUT if you are seeking to reduced or reamortize your monthly payments to reflect the large payments there will be additional costs.  So, as a means to reduce your costs and give you the flexibility to make an annual payment no greater than 20%, I would look at an interest only product.  This should solve your issue.