ADS.Route (yaads v0.1.0)

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A route of a TwinCAT system, as its system service lists them, one entry at a time, for ADS.Client.routes/2: index group 803, SYSTEMSERVICE_ENUMREMOTE in Beckhoff's Tc2_Utilities, on AMS port 10000, the entry's index as the offset. After the last, the system answers :device_no_more_handles.

Beckhoff documents the index group, and the fields of a route (ST_AmsRouteEntry), but not how an entry comes; this layout is as TwinCAT 3.1 4026 answers. All numbers are little-endian:

BytesField
6the route's AMS NetId
2its transport, 1 for TCP/IP
4its flags
4its timeout, in ms
16zeros
4, 4, 4the lengths of its address, its name, and a third string, each with a zero after
...the address, the name, and the third, empty on every route seen

Of the flags, Beckhoff names 0x1, temporary, 0x2, dynamic, a host name rather than an address, and 0x4, not to be overridden (see flags/1); TwinCAT sets others as well, such as 0x8 and 0x40, which it doesn't name. The strings are in the system's code page, Windows-1252 unless told otherwise (see ADS.Codepage).

Summary

Types

t()

Functions

decode(bytes, codepage \\ Codepage.default())

A route from the bytes of an entry, or :error if they don't make one.

flags(route)

The flags of a route that Beckhoff names, and :unknown with the bits it doesn't, if any.

Types

t()

@type t() :: %ADS.Route{
  address: String.t(),
  flags: non_neg_integer(),
  name: String.t(),
  net_id: ADS.net_id(),
  timeout: non_neg_integer(),
  transport: atom() | non_neg_integer()
}

Functions

decode(bytes, codepage \\ Codepage.default())

@spec decode(binary(), ADS.Codepage.t()) :: {:ok, t()} | :error

A route from the bytes of an entry, or :error if they don't make one.

iex> entry =
...>   <<10, 0, 0, 7, 1, 1, 1::16-little, 0::32, 60_000::32-little, 0::128, 9::32-little,
...>     6::32-little, 0::32, "10.0.0.7", 0, "scada", 0>>
iex> ADS.Route.decode(entry)
{:ok, %ADS.Route{name: "scada", net_id: "10.0.0.7.1.1", address: "10.0.0.7",
                 transport: :tcp_ip, flags: 0, timeout: 60_000}}

flags(route)

@spec flags(t()) :: [:temporary | :dynamic | :no_override | {:unknown, pos_integer()}]

The flags of a route that Beckhoff names, and :unknown with the bits it doesn't, if any.

iex> ADS.Route.flags(%ADS.Route{flags: 0x41})
[:temporary, {:unknown, 0x40}]