Grizzly (grizzly v0.16.1) View Source
Send commands to Z-Wave devices
Grizzly provides the send_command
function as the way to send a command to
Z-Wave devices.
The send_command
function takes the node id that you are trying to send a
command to, the command name, and optionally command arguments and command
options.
A basic command that has no options or arguments looks like this:
Grizzly.send_command(node_id, :switch_binary_get)
A command with command arguments:
Grizzly.send_command(node_id, :switch_binary_set, value: :off)
Also, a command can have options.
Grizzly.send_command(node_id, :switch_binary_get, [], timeout: 10_000, retries: 5)
Some possible return values from send_command
are:
{:ok, Grizzly.Report.t()}
- the command was sent and the Z-Wave device responded with a report. SeeGrizzly.Report
for more information.{:error, :including}
- current the Z-Wave controller is adding or removing a device and commands cannot be processed right now{:error, :firmware_updating}
- current the Z-Wave controller is updating firmware and commands cannot be processed right now{:error, reason}
- there was some other reason for an error, two common ones are::nack_response
For a more detailed explanation of the responses from a send_command
call
see the typedoc for Grizzly.send_command_response()
.
Events from Z-Wave
Events generating from a Z-Wave device, for example a motion detected event,
can be handled via the Grizzly.subscribe_command/1
and
Grizzly.subscribe_commands/1
functions. This will allow you to subscribe
to specific commands. When the command is received from the Z-Wave network
it will placed in a Grizzly.Report
and set to the subscribing process. The
node that generated the report can be accessed with the :node_id
field in
the report.
iex> Grizzly.subscribe_command(:battery_report)
# sometime latter
iex> flush
{:grizzly, :event, %Grizzly.Report{command: %Grizzly.ZWave.Command{name: :battery_report}}}
Link to this section Summary
Functions
List the command for a particular command class
List the support commands
Send a raw binary to the Z-Wave node
Send a command to the node via the node id or to Z/IP Gateway
Subscribe to a command event from a Z-Wave device
Subscribe to many events from a Z-Wave device
Unsubscribe to an event
Link to this section Types
Specs
command() :: atom()
Specs
command_opt() :: {:timeout, non_neg_integer()} | {:retries, non_neg_integer()} | {:handler, handler()} | {:transmission_stats, boolean()}
Specs
A custom handler for the command.
See Grizzly.CommandHandler
behaviour for more documentation.
Specs
node_id() :: non_neg_integer()
Specs
send_command_response() :: {:ok, Grizzly.Report.t()} | {:error, :including | :updating_firmware | :nack_response | any()}
The response from sending a Z-Wave command
When everything is okay the response will be {:ok, Grizzly.Report{}}
. For
documentation about a report see Grizzly.Report
module.
When there are errors the response will be in the pattern of
{:error, reason}
.
Three reasons that Grizzly supports for all commands are :nack_response
,
:update_firmware
, and :including
.
A :nack_response
normally means that the Z-Wave node that you were trying
to send a command to is unreachable and did not receive your command at all.
This could mean that the Z-Wave network is overloaded and you should reissue
the command, the device is too far from the controller, or the device is no
longer part of the Z-Wave network.
Grizzly by default will try a command 3 times before sending returning a
:nack_response
. This is configurable via the :retries
command option in
the Grizzly.send_command/4
function. This is useful if you are going to
have a known spike in Z-Wave traffic.
In you receive the reason for the error to be :including
that means the
controller is in an inclusion state and your command will be dropped if we
tried to send it. So we won't allow sending a Z-Wave command during an
inclusion. It's best to wait and try again once your application is done
trying to include.
Specs
seq_number() :: non_neg_integer()
Link to this section Functions
Specs
List the command for a particular command class
Specs
list_commands() :: [atom()]
List the support commands
Specs
send_binary(Grizzly.ZWave.node_id(), binary()) :: :ok | {:error, :including | :firmware_updating}
Send a raw binary to the Z-Wave node
This function does not block and expects the sending process to handle the lifecycle of the command being sent. This maximizes control but minimizes safety and puts things such as timeouts, retries, and response handling in the hand of the calling process.
When sending the binary ensure the binary is the encoded
Grizzly.ZWave.Commands.ZIPPacket
.
seq_no = 0x01
{:ok, my_command} = Grizzly.ZWave.Commands.SwitchBinaryGet.new()
{:ok, packet} = Grizzly.ZWave.Commands.ZIPPacket.with_zwave_command(my_command, seq_no)
binary = Grizzly.ZWave.to_binary(packet)
Grizzly.send_binary(node_id, binary)
This is helpful when you need very fine grade control of the Z/IP Packet or if you not expecting a response from a Z-Wave network to handle the back and forth between your application and the Z-Wave network. Also, this can be useful for debugging purposes.
First check if send_command/4
will provide the functionality that is needed
before using this function.
After sending a binary packet the calling process will receive messages in the form of:
{:grizzly, :binary_response, binary}
Specs
send_command(Grizzly.ZWave.node_id() | :gateway, command(), args :: list(), [ command_opt() ]) :: send_command_response()
Send a command to the node via the node id or to Z/IP Gateway
To talk to your controller directly you can pass :gateway
as the node id.
This is helpful because your controller might not always be the same node id
on any given network. This ensures that not matter node id your controller is
you will still be able to query it and make it perform Z-Wave functions. There
are many Z-Wave functions a controller do. There are helper functions for
these functions in Grizzly.Network
and Grizzly.Node
.
Specs
subscribe_command(command()) :: :ok
Subscribe to a command event from a Z-Wave device
Specs
subscribe_commands([command()]) :: :ok
Subscribe to many events from a Z-Wave device
Specs
unsubscribe_command(command()) :: :ok
Unsubscribe to an event