# 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)
```

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