CND-DET routines 3/8

 BBS: Inland Empire Archive
Date: 03-25-93 (15:33)             Number: 288
From: DIRK THEURER                 Refer#: NONE
  To: ALL                           Recvd: NO  
Subj: CND-DET routines 3/8           Conf: (2) Quik_Bas
' CND-DET routines (part 3)
  ' Notes:
  '  - I have NO idea why an "End of transmission" (ASCII 4) is used to
  '    signal the START of the actual phone number data stream!... and
  '    nothing is used to signal the actual END of data! What gives?!?!
  '  - number of characters in data indicates exactly how many characters
  '    there are between itself and the CRC value
  '  - phone number data can be single character indicating some "other"
  '    condition on the data:
  '    - out of area (a single upper-case O)
  '    - private (a single upper-case P)
  '    - others??? (I haven't seen any yet)
  '  - I have not been able to completely figure out how the CRC is
  '    calculated. I got this 'explanation' from a friend:
  '      "The CRC is the twos compliment of the modulo 256 sum of the other
  '      words in the data message". I suppose that the 'data message' is
  '      just the date/time/phone number portion...???
  '  - I've recently received a CRC routine that might work for the CRC
  '    portion of CND data. I've placed in a commented block near where it
  '    would "do the most good". Thanks go to Quinn Tyler Jackson for the
  '    'snippet'!
DIM Private AS INTEGER DIM OutOfArea AS INTEGER DIM PreviousNo AS INTEGER DIM CTRLD AS INTEGER DIM NoOfUs AS INTEGER DIM Junk AS INTEGER DIM DataLength AS INTEGER DIM CNDData AS STRING DIM TempCRCSum AS LONG Private = False OutOfArea = False PreviousNo = False CTRLD = False NoOfUs = 0 Junk = False DataLength = 0 CNDData = "" ' ' initialize CND data ' CND.CNDAttrib = 0 CND.CNDDate = "" CND.CNDTime = "" CND.CNDNumber = "" CND.CNDCRC = 0 CND.CNDName = "" CND.CNDOther = 0 ' ' Continues... ' --- * Origin: RAVE * Burnaby, BC (1:153/810)
Outer Court
Echo Basic Postings

Books at Amazon:

Back to BASIC: The History, Corruption, and Future of the Language

Hackers: Heroes of the Computer Revolution (including Tiny BASIC)

Go to: The Story of the Math Majors, Bridge Players, Engineers, Chess Wizards, Scientists and Iconoclasts who were the Hero Programmers of the Software Revolution

The Advent of the Algorithm: The Idea that Rules the World

Moths in the Machine: The Power and Perils of Programming

Mastering Visual Basic .NET