[TrunkCom] Converting Talkgroups

[Wayne M H]

On Fri, 31 May 2002 17:06:58 -0400, Michael Wallach
<mjwallach@earthlink.net> wrote:

>Does anyone know how to convert a Type I talkgroup to the number that=20
>displays when the scanner is set up for Type II?

You'll have one problem...that being you'll need the radio id to
exactly determine the Type II id.

Take a look here. Specifically the table containing the breakdown of
bits for Type I.

http://tricari.home.attbi.com/protocols.html

The Type II value is the raw combination of block, fleet, sub-fleet,
and radio id. Without the radio id you can only figure out the range
the Type II id would fall under.

Here's an example...

Using Sizecode C and a Type I id of 707-2.

C is broken down as "aaabbbcccddddddd"

a=3Dblock, b=3Dfleet, c=3Dsub-fleet, and d=3Dradio id

You have to then convert the Type I id to binary. Keep in mind that
you don't convert 709 to binary, you do first the 7, then the 9, as it
isn't seven hundred-nine it's seven and nine, then the sub-fleet. We
don't know the radio id so we'll just null it with zeros.

Bin: 111-111-010-0000000
Decimal: 7-7-2-0

Decimal Type II: 64768

Then change the radio id portion to all ones to find your maximum.

Bin: 111-111-010-1111111
Decimal: 7-7-2-127

Decimal Type II: 64895

If you know the radio id, then just plug it in, just keep your number
base (hex or decimal) correct.

Let me know if you have any questions.

Wayne