View source for AlphaNet Data Protocol

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The '''AlphaCom/AlphaNet Data Protocol''' (ACDP protocol) is used for: 
* Data communication between AlphaCom Exchanges in AlphaNet, including other types of exchanges such as [[TouchLine]] MPC
* Data communication between AlphaCom Exchanges and External Devices such as [[RIO]]s and PC based Control Handlers
* Advanced internal control of the AlphaCom. [[Event Handler]] can use DP messages as general [[Event Handler#Action Commands|Action Commands]].

The Data Protocol is made generally available from software version AMC 06.00. Previous AMC softwares are NOT compatible with this protocol descriptions.


=== Protocol properties ===
* '''Binary format''' for speed. Readable ASCII hex format can be used as an alternative for easier debugging
* The '''[[physical layer]]''' of the protocol is RS485, RS422 or RS232. In AlphaCom E the protocol can also be encapsulated in TCP/IP. 
* '''[[Data link layer]]s''' with message checksum for reliability, and with acknowledgment and re-transmission of erroneous messages
* '''[[Network layer]]''' for routability when several exchanges are connected
* '''Variable length fields''' and optional fields so that the protocol can be used also in future systems with different requirements regarding number of digits in addresses, station numbers etc.
* A systematic way of '''addressing exchange resources''' both as directory numbers and physical addresses
* '''Addressed messages'''. Commands are addressed to a specific [[device]], and response is returned to the device issuing the command only. In addition, there is a few status [[Broadcast messages (ACDP) |broadcast messages]]
* Addressed messages can be '''routed in a network'''. The input and output messages have identical frame format, and thus can be sent via transit exchanges. The same protocol is used both to control a single exchange, and as the AlphaNet protocol<br>

=== Message example ===
Here is a HEX coded example of a message with network layer header and application data. This is basically what you send to the exchange in the “simple link layer” format.
We assume that you use exchange node 01, the PC is device 01, and that there is a station 107 and 102.
The message [[DIAL_DIGITS]] looks like this, with spaces between fields for clarity only:

 Network        Application   Application Message 
 <u>layer header</u>   <u>header      </u>  <u>parameters&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</u>         
 <u>0101</u> <u>0141</u> <u>01</u>   <u>41</u> <u>1234</u> <u>0050</u>  <u>3201107F</u> <u>20102F</u>
 Src  Dest Hop  Cl Ref  Msg   P1       P2
 <u>dev </u> <u>dev </u> <u>cn</u>t  <u>ss</u> <u>    </u> <u>id  </u>  <u>Station </u> <u>Digits</u> to dial

=== Message Formats ===
* [[Message Formats - Grouped by Function]]
* [[Message Formats (Sortable)]]
* [[Explanation of message format]]


[[Category:Protocols]]
[[Category:ACDP messages]]