Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    Name or NavList Code:
    Email:
       
    Reply
    Re: Calculator question
    From: Bill Murdoch
    Date: 2005 Feb 21, 09:53 EST
    In a message dated 2/19/05 7:37:25 P.M. Eastern Standard Time, FrankReedCT@AOL.COM writes:
    The most recent TI-89 has something like 3 megabytes of memory. It can take simple programming and also relatively sophisticated code, and they do *symbolic* algebra, trig, and differentiation and integration, too. But no solar power
    3 MB is far more memory than is really necessary for a celestial navigation calculator unless you write software like one of Bill Gates's employees.  Here are the memory requirements used in a TI-82 program that I wrote in the early 1990's using TI basic.
     
    To input time and convert to a single unit - 468 bytes
    To calculate a few time dependent constants - 227 bytes
    To input a position - 400 bytes
    To calculate almanac data to +/- 0.01 (2 S.D.) accuracy -
       Sun - 650 bytes
       Moon - 1448 bytes
       93 stars - 1682 bytes for data and 632 bytes for the program
       Planets - 411 bytes
             plus for each planet:
          Venus - 555 bytes
          Mars - 964 bytes
          Jupiter - 1451 bytes
          Saturn - 1879 bytes
       Input sextant and other sight data - 796 bytes
       Convert R.A. to GHA - 146 bytes
       Reduce the sight - 201 bytes
       Display the azimuth and intercept - 191 bytes
     
    The whole program which does almost everything I could think of except lunars fits in a 28 KB memory.
     
    I too think it would be nice to have solar power and be free of the batteries.
     
    Bill Murdoch
     
         
     
     
       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site