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Where can I find protocol documentation?


George M0GXB
 

For starters, I would like to find a full, complete, and correct documentation for whatever the protocol is called (IPSC, HBLINK, ??) that things like MMDVM use to talk to the gateways.

I found an old (2015) document somewhere which is clearly an early alpha version and with errors too, but the actual data streams I am looking at are for something that has evolved a bit since then. So where is this specified?

And is that protocol used for any other links in the growing DV networks?

George M0GXB


Steve N4IRS
 

George,
As far as I know, you have found all of the "documentation" on the protocol called HBP. MMDVM uses a slightly modified version of HBP to communicate with DMRGateway and networks like BM, XLX and DMR Plus. This is DMR only. To understand that protocol since it's open source, you can look at the source code for MMDVMHost, DMRGateway, HBlink and XLX.  You can also take a look at <https://github.com/marrold/MMDVM-Dissector>

For NXDN, D-Star, YSF and P25 see the source to MMDVMHost.

Hope this helps.
73, Steve N4IRS

On 11/3/2020 12:25 PM, George wrote:
For starters, I would like to find a full, complete, and correct documentation for whatever the protocol is called (IPSC, HBLINK, ??) that things like MMDVM use to talk to the gateways.

I found an old (2015) document somewhere which is clearly an early alpha version and with errors too, but the actual data streams I am looking at are for something that has evolved a bit since then. So where is this specified?

And is that protocol used for any other links in the growing DV networks?

George M0GXB


George M0GXB
 

Is that seriously as good as it gets??

Code is not documentation - and in my experience it is usually pretty unreadable anyway, being written in a crap language like C I expect.
I do not understand how people expect systems to be interoperable if the protocols used are not well documented - or is that why I so often hear about "weird problems" and things not quite working right?
Someone tried back in 2015, presumably when making a start. Shame it wasn't maintained unless I am just not finding it.

I am getting too old for this. When I started programming the ASCII text of the documentation would be bigger than the code itself!!

73 George M0GXB


Steve N4IRS
 

So read the python.

Sent by smoke signal (AT&T)


From: main@DVSwitch.groups.io <main@DVSwitch.groups.io> on behalf of George <gmb2005@...>
Sent: Tuesday, November 3, 2020 4:44:41 PM
To: main@DVSwitch.groups.io <main@DVSwitch.groups.io>
Subject: Re: [DVSwitch] Where can I find protocol documentation?
 
Is that seriously as good as it gets??

Code is not documentation - and in my experience it is usually pretty unreadable anyway, being written in a crap language like C I expect.
I do not understand how people expect systems to be interoperable if the protocols used are not well documented - or is that why I so often hear about "weird problems" and things not quite working right?
Someone tried back in 2015, presumably when making a start. Shame it wasn't maintained unless I am just not finding it.

I am getting too old for this. When I started programming the ASCII text of the documentation would be bigger than the code itself!!

73 George M0GXB