From 0c333567f599206cb0be6b74f02e59820536e0b2 Mon Sep 17 00:00:00 2001 From: cbdev Date: Sun, 31 Mar 2019 09:00:12 +0200 Subject: Move backend documentation out of main README --- backends/artnet.md | 41 ++++++++++++++++++++++++++ backends/evdev.md | 72 ++++++++++++++++++++++++++++++++++++++++++++++ backends/loopback.md | 28 ++++++++++++++++++ backends/midi.md | 54 +++++++++++++++++++++++++++++++++++ backends/ola.md | 41 ++++++++++++++++++++++++++ backends/osc.md | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++ backends/sacn.md | 58 +++++++++++++++++++++++++++++++++++++ 7 files changed, 375 insertions(+) create mode 100644 backends/artnet.md create mode 100644 backends/evdev.md create mode 100644 backends/loopback.md create mode 100644 backends/midi.md create mode 100644 backends/ola.md create mode 100644 backends/osc.md create mode 100644 backends/sacn.md (limited to 'backends') diff --git a/backends/artnet.md b/backends/artnet.md new file mode 100644 index 0000000..90a7697 --- /dev/null +++ b/backends/artnet.md @@ -0,0 +1,41 @@ +### The `artnet` backend + +The ArtNet backend provides read-write access to the UDP-based ArtNet protocol for lighting +fixture control. + +#### Global configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `bind` | `127.0.0.1 6454` | none | Binds a network address to listen for data. This option may be set multiple times, with each interface being assigned an index starting from 0 to be used with the `interface` instance configuration option. At least one interface is required for transmission. | +| `net` | `0` | `0` | The default net to use | + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `net` | `0` | `0` | ArtNet `net` to use | +| `universe` | `0` | `0` | Universe identifier | +| `destination` | `10.2.2.2` | none | Destination address for sent ArtNet frames. Setting this enables the universe for output | +| `interface` | `1` | `0` | The bound address to use for data input/output | + +#### Channel specification + +A channel is specified by it's universe index. Channel indices start at 1 and end at 512. + +Example mapping: +``` +net1.231 < net2.123 +``` + +A 16-bit channel (spanning any two normal 8-bit channels in the same universe, also called a wide channel) may be mapped with the syntax +``` +net1.1+2 > net2.5+123 +``` + +A normal channel that is part of a wide channel can not be mapped individually. + +#### Known bugs / problems + +The minimum inter-frame-time is disregarded, as the packet rate is determined by the rate of incoming +channel events. \ No newline at end of file diff --git a/backends/evdev.md b/backends/evdev.md new file mode 100644 index 0000000..dfe5ec9 --- /dev/null +++ b/backends/evdev.md @@ -0,0 +1,72 @@ +### The `evdev` backend + +This backend allows using Linux `evdev` devices such as mouses, keyboards, gamepads and joysticks +as input and output devices. All buttons and axes available to the Linux system are mappable. +Output is provided by the `uinput` kernel module, which allows creation of virtual input devices. +This functionality may require elevated privileges (such as special group membership or root access). + +#### Global configuration + +This backend does not take any global configuration. + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|---------------|-------------------------------------------------------| +| `device` | `/dev/input/event1` | none | `evdev` device to use as input device | +| `input` | `Xbox Wireless` | none | Presentation name of evdev device to use as input (prefix-matched) | +| `output` | `My Input Device` | none | Output device presentation name. Setting this option enables the instance for output | +| `exclusive` | `1` | `0` | Prevent other processes from using the device | +| `id` | `0x1 0x2 0x3` | none | Set output device bus identification (Vendor, Product and Version), optional | +| `axis.AXISNAME`| `34300 0 65536 255 4095` | none | Specify absolute axis details (see below) for output. This is required for any absolute axis to be output. + +The absolute axis details configuration (e.g. `axis.ABS_X`) is required for any absolute axis on output-enabled +instances. The configuration value contains, space-separated, the following values: + +* `value`: The value to assume for the axis until an event is received +* `minimum`: The axis minimum value +* `maximum`: The axis maximum value +* `fuzz`: A value used for filtering the input stream +* `flat`: An offset, below which all deviations will be ignored +* `resolution`: Axis resolution in units per millimeter (or units per radian for rotational axes) + +For real devices, all of these parameters for every axis can be found by running `evtest` on the device. + +#### Channel specification + +A channel is specified by its event type and event code, separated by `.`. For a complete list of event types and codes +see the [kernel documentation](https://www.kernel.org/doc/html/v4.12/input/event-codes.html). The most interesting event types are + +* `EV_KEY` for keys and buttons +* `EV_ABS` for absolute axes (such as Joysticks) +* `EV_REL` for relative axes (such as Mouses) + +The `evtest` tool is useful to gather information on devices active on the local system, including names, types, codes +and configuration supported by these devices. + +Example mapping: +``` +ev1.EV_KEY.KEY_A > ev1.EV_ABS.ABS_X +``` + +Note that to map an absolute axis on an output-enabled instance, additional information such as the axis minimum +and maximum are required. These must be specified in the instance configuration. When only mapping the instance +as a channel input, this is not required. + +#### Known bugs / problems + +Creating an `evdev` output device requires elevated privileges, namely, write access to the system's +`/dev/uinput`. Usually, this is granted for users in the `input` group and the `root` user. + +Input devices may synchronize logically connected event types (for example, X and Y axes) via `EV_SYN`-type +events. The MIDIMonster also generates these events after processing channel events, but may not keep the original +event grouping. + +Relative axes (`EV_REL`-type events), such as generated by mouses, are currently handled in a very basic fashion, +generating only the normalized channel values of `0`, `0.5` and `1` for any input less than, equal to and greater +than `0`, respectively. As for output, only the values `-1`, `0` and `1` are generated for the same interval. + +`EV_KEY` key-down events are sent for normalized channel values over `0.9`. + +Extended event type values such as `EV_LED`, `EV_SND`, etc are recognized in the MIDIMonster configuration file +but may or may not work with the internal channel mapping and normalization code. \ No newline at end of file diff --git a/backends/loopback.md b/backends/loopback.md new file mode 100644 index 0000000..a06c768 --- /dev/null +++ b/backends/loopback.md @@ -0,0 +1,28 @@ +### The `loopback` backend + +This backend allows the user to create logical mapping channels, for example to exchange triggering +channels easier later. All events that are input are immediately output again on the same channel. + +#### Global configuration + +All global configuration is ignored. + +#### Instance configuration + +All instance configuration is ignored + +#### Channel specification + +A channel may have any string for a name. + +Example mapping: +``` +loop.foo < loop.bar123 +``` + +#### Known bugs / problems + +It is possible (and very easy) to configure loops using this backend. Triggering a loop +will create a deadlock, preventing any other backends from generating events. +Be careful with bidirectional channel mappings, as any input will be immediately +output to the same channel again. \ No newline at end of file diff --git a/backends/midi.md b/backends/midi.md new file mode 100644 index 0000000..7d3e847 --- /dev/null +++ b/backends/midi.md @@ -0,0 +1,54 @@ +### The `midi` backend + +The MIDI backend provides read-write access to the MIDI protocol via virtual ports. + +#### Global configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `name` | `MIDIMonster` | none | MIDI client name | + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `read` | `20:0` | none | MIDI device to connect for input | +| `write` | `DeviceName` | none | MIDI device to connect for output | + +MIDI device names may either be `client:port` portnames or prefixes of MIDI device names. +Run `aconnect -i` to list input ports and `aconnect -o` to list output ports. + +Each instance also provides a virtual port, so MIDI devices can also be connected with `aconnect `. + +#### Channel specification + +The MIDI backend supports multiple channel types + +* `cc` - Control Changes +* `note` - Note On/Off messages +* `nrpn` - NRPNs (not yet implemented) + +A channel is specified using the syntax `channel.`. The shorthand `ch` may be used instead +of `channel`. +The earlier syntax of `.` is officially deprecated but still supported for compatability +reasons. This support may be removed at some future time. + +Channels range from `0` to `15`. Each channel consists of 128 notes (numbered `0` through `127`) and 128 CC's +(numbered likewise), a channel pressure control (also called 'channel aftertouch') and a pitch control. +Each Note also has an additional pressure value associated with it. + +Example mappings: +``` +midi1.ch0.note9 > midi2.channel1.cc4 +midi1.channel15.cc1 > midi1.channel0.note0 +``` +#### Known bugs / problems + +Currently, no Note Off messages are sent (instead, Note On messages with a velocity of 0 are +generated, which amount to the same thing according to the spec). This may be implemented as +a configuration option at a later time. + +NRPNs are not yet fully implemented, though rudimentary support is in the codebase. + +To see which events your MIDI devices output, ALSA provides the `aseqdump` utility. You can +list all incoming events using `aseqdump -p `. \ No newline at end of file diff --git a/backends/ola.md b/backends/ola.md new file mode 100644 index 0000000..e3a1197 --- /dev/null +++ b/backends/ola.md @@ -0,0 +1,41 @@ +### The `ola` backend + +This backend connects the MIDIMonster to the Open Lighting Architecture daemon. This can be useful +to take advantage of additional protocols implemented in OLA. This backend is currently marked as +optional and is only built with `make full` in the `backends/` directory, as the OLA is a large +dependency to require for all users. + +#### Global configuration + +This backend does not take any global configuration. + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|---------------|-------------------------------------------------------| +| `universe` | `7` | `0` | OLA universe to send/receive data on | + +#### Channel specification + +A channel is specified by it's universe index. Channel indices start at 1 and end at 512. + +Example mapping: +``` +ola1.231 < in2.123 +``` + +A 16-bit channel (spanning any two normal 8-bit channels in the same universe, also called a wide channel) may be mapped with the syntax +``` +ola1.1+2 > net2.5+123 +``` + +A normal channel that is part of a wide channel can not be mapped individually. + +#### Known bugs / problems + +The backend currently assumes that the OLA daemon is running on the same host as the MIDIMonster. +This may be made configurable in the future. + +This backend requires `libola-dev` to be installed, which pulls in a rather large and aggressive (in terms of probing +and taking over connected hardware) daemon. It is thus marked as optional and only built when executing the `full` target +within the `backends` directory. \ No newline at end of file diff --git a/backends/osc.md b/backends/osc.md new file mode 100644 index 0000000..c784cda --- /dev/null +++ b/backends/osc.md @@ -0,0 +1,81 @@ +### The `osc` backend + +This backend offers read and write access to the Open Sound Control protocol, +spoken primarily by visual interface tools and hardware such as TouchOSC. + +#### Global configuration + +This backend does not take any global configuration. + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `root` | `/my/osc/path` | none | An OSC path prefix to be prepended to all channels | +| `bind` | `:: 8000` | none | The host and port to listen on | +| `destination` | `10.11.12.13 8001` | none | Remote address to send OSC data to. Setting this enables the instance for output. The special value `learn` causes the MIDImonster to always reply to the address the last incoming packet came from. A different remote port for responses can be forced with the syntax `learn@` | + +Note that specifying an instance root speeds up matching, as packets not matching +it are ignored early in processing. + +Channels that are to be output or require a value range different from the default ranges (see below) +require special configuration, as their types and limits have to be set. + +This is done in the instance configuration using an assignment of the syntax + +``` +/local/osc/path = ... +``` + +The OSC path to be configured must only be the local part (omitting a configured instance root). + +**format** may be any sequence of valid OSC type characters. See below for a table of supported +OSC types. + +For each component of the path, the minimum and maximum values must be given separated by spaces. +Components may be accessed in the mapping section as detailed in the next section. + +An example configuration for transmission of an OSC message with 2 floating point components with +a range between 0.0 and 2.0 (for example, an X-Y control), would look as follows: + +``` +/1/xy1 = ff 0.0 2.0 0.0 2.0 +``` + +#### Channel specification + +A channel may be any valid OSC path, to which the instance root will be prepended if +set. Multi-value controls (such as X-Y pads) are supported by appending `:n` to the path, +where `n` is the parameter index, with the first (and default) one being `0`. + +Example mapping: +``` +osc1./1/xy1:0 > osc2./1/fader1 +``` + +Note that any channel that is to be output will need to be set up in the instance +configuration. + +#### Supported types & value ranges + +OSC allows controls to have individual value ranges and supports different parameter types. +The following types are currently supported by the MIDImonster: + +* **i**: 32-bit signed integer +* **f**: 32-bit IEEE floating point +* **h**: 64-bit signed integer +* **d**: 64-bit double precision floating point + +For each type, there is a default value range which will be assumed if the channel is not otherwise +configured using the instance configuration. Values out of a channels range will be clipped. + +The default ranges are: + +* **i**: `0` to `255` +* **f**: `0.0` to `1.0` +* **h**: `0` to `1024` +* **d**: `0.0` to `1.0` + +#### Known bugs / problems + +Ping requests are not yet answered. There may be some problems using broadcast output and input. \ No newline at end of file diff --git a/backends/sacn.md b/backends/sacn.md new file mode 100644 index 0000000..3d245a4 --- /dev/null +++ b/backends/sacn.md @@ -0,0 +1,58 @@ +### The `sacn` backend + +The sACN backend provides read-write access to the Multicast-UDP based streaming ACN protocol (ANSI E1.31-2016), +used for lighting fixture control. The backend sends universe discovery frames approximately every 10 seconds, +containing all write-enabled universes. + +#### Global configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `name` | `sACN source` | `MIDIMonster` | sACN source name | +| `cid` | `0xAA 0xBB 0xCC` ... | `MIDIMonster` | Source CID (16 bytes) | +| `bind` | `0.0.0.0 5568` | none | Binds a network address to listen for data. This option may be set multiple times, with each descriptor being assigned an index starting from 0 to be used with the `interface` instance configuration option. At least one descriptor is required for transmission. | + +#### Instance configuration + +| Option | Example value | Default value | Description | +|---------------|-----------------------|-----------------------|-----------------------| +| `universe` | `0` | none | Universe identifier | +| `interface` | `1` | `0` | The bound address to use for data input/output | +| `priority` | `100` | none | The data priority to transmit for this instance. Setting this option enables the instance for output and includes it in the universe discovery report. | +| `destination` | `10.2.2.2` | Universe multicast | Destination address for unicast output. If unset, the multicast destination for the specified universe is used. | +| `from` | `0xAA 0xBB` ... | none | 16-byte input source CID filter. Setting this option filters the input stream for this universe. | +| `unicast` | `1` | `0` | Prevent this instance from joining its universe multicast group | + +Note that instances accepting multicast input also process unicast frames directed at them, while +instances in `unicast` mode will not receive multicast frames. + +#### Channel specification + +A channel is specified by it's universe index. Channel indices start at 1 and end at 512. + +Example mapping: +``` +sacn1.231 < sacn2.123 +``` + +A 16-bit channel (spanning any two normal 8-bit channels in the same universe, also called a wide channel) may be mapped with the syntax +``` +sacn.1+2 > sacn2.5+123 +``` + +A normal channel that is part of a wide channel can not be mapped individually. + +#### Known bugs / problems + +The DMX start code of transmitted and received universes is fixed as `0`. + +The (upper) limit on packet transmission rate mandated by section 6.6.1 of the sACN specification is disregarded. +The rate of packet transmission is influenced by the rate of incoming mapped events on the instance. + +Universe synchronization is currently not supported, though this feature may be implemented in the future. + +To use multicast input, all networking hardware in the path must support the IGMPv2 protocol. + +The Linux kernel limits the number of multicast groups an interface may join to 20. An instance configured +for input automatically joins the multicast group for its universe, unless configured in `unicast` mode. +This limit can be raised by changing the kernel option in `/proc/sys/net/ipv4/igmp_max_memberships`. \ No newline at end of file -- cgit v1.2.3