{
  "name": "Dot Matrix",
  "status": "rc",
  "shortId": "dotmatrix",
  "camelName": "dotMatrix",
  "shortName": "dotMatrix",
  "extends": [
    "_base"
  ],
  "notes": {
    "short": "A rectangular dot matrix display, made of monochrome LEDs or Braille pins."
  },
  "classIdentifier": 286070091,
  "enums": {
    "Variant": {
      "name": "Variant",
      "storage": 1,
      "members": {
        "LED": 1,
        "Braille": 2
      }
    }
  },
  "constants": {},
  "packets": [
    {
      "kind": "report",
      "name": "command_not_implemented",
      "identifier": 3,
      "description": "This report may be emitted by a server in response to a command (action or register operation)\nthat it does not understand.\nThe `service_command` and `packet_crc` fields are copied from the command packet that was unhandled.\nNote that it's possible to get an ACK, followed by such an error report.",
      "fields": [
        {
          "name": "service_command",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        },
        {
          "name": "packet_crc",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        }
      ],
      "identifierName": "command_not_implemented",
      "packFormat": "u16 u16",
      "derived": "_base"
    },
    {
      "kind": "const",
      "name": "instance_name",
      "identifier": 265,
      "description": "A friendly name that describes the role of this service instance in the device.\nIt often corresponds to what's printed on the device:\nfor example, `A` for button A, or `S0` for servo channel 0.\nWords like `left` should be avoided because of localization issues (unless they are printed on the device).",
      "fields": [
        {
          "name": "_",
          "type": "string",
          "storage": 0
        }
      ],
      "optional": true,
      "identifierName": "instance_name",
      "packFormat": "s",
      "derived": "_base"
    },
    {
      "kind": "ro",
      "name": "status_code",
      "identifier": 259,
      "description": "Reports the current state or error status of the device. ``code`` is a standardized value from \nthe Jacdac status/error codes. ``vendor_code`` is any vendor specific error code describing the device\nstate. This report is typically not queried, when a device has an error, it will typically\nadd this report in frame along with the announce packet. If a service implements this register,\nit should also support the ``status_code_changed`` event defined below.",
      "fields": [
        {
          "name": "code",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        },
        {
          "name": "vendor_code",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        }
      ],
      "optional": true,
      "identifierName": "status_code",
      "packFormat": "u16 u16",
      "derived": "_base"
    },
    {
      "kind": "rw",
      "name": "client_variant",
      "identifier": 9,
      "description": "An optional register in the format of a URL query string where the client can provide hints how\nthe device twin should be rendered. If the register is not implemented, the client library can simulate the register client side.",
      "fields": [
        {
          "name": "_",
          "type": "string",
          "storage": 0
        }
      ],
      "optional": true,
      "identifierName": "client_variant",
      "packFormat": "s",
      "derived": "_base"
    },
    {
      "kind": "event",
      "name": "status_code_changed",
      "identifier": 4,
      "description": "Notifies that the status code of the service changed.",
      "fields": [
        {
          "name": "code",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        },
        {
          "name": "vendor_code",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        }
      ],
      "optional": true,
      "identifierName": "status_code_changed",
      "packFormat": "u16 u16",
      "derived": "_base"
    },
    {
      "kind": "rw",
      "name": "dots",
      "identifier": 2,
      "description": "The state of the screen where dot on/off state is\nstored as a bit, column by column. The column should be byte aligned.\n\nFor example, if the display has no more than 8 rows in each column, then each byte contains bits corresponding\nto a single column. Least-significant bit is on top.\nIf display has 10 rows, then each column is represented by two bytes.\nThe top-most 8 rows sit in the first byte (with the least significant bit being on top),\nand the remainign 2 row sit in the second byte.\n\nThe following C expression can be used to check if a given `column, row` coordinate is set:\n`dots[column * column_size + (row >> 3)] & (1 << (row & 7))`, where\n`column_size` is `(number_of_rows + 7) >> 3` (note that if number of rows is 8 or less then `column_size` is `1`),\nand `dots` is of `uint8_t*` type.\n\nThe size of this register is `number_of_columns * column_size` bytes.",
      "fields": [
        {
          "name": "_",
          "type": "bytes",
          "storage": 0,
          "isSimpleType": true
        }
      ],
      "identifierName": "value",
      "packFormat": "b"
    },
    {
      "kind": "rw",
      "name": "brightness",
      "identifier": 1,
      "description": "Reads the general brightness of the display, brightness for LEDs. `0` when the screen is off.",
      "fields": [
        {
          "name": "_",
          "unit": "/",
          "shift": 8,
          "type": "u0.8",
          "storage": 1
        }
      ],
      "optional": true,
      "identifierName": "intensity",
      "packFormat": "u0.8"
    },
    {
      "kind": "const",
      "name": "rows",
      "identifier": 385,
      "description": "Number of rows on the screen",
      "fields": [
        {
          "name": "_",
          "unit": "#",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        }
      ],
      "packFormat": "u16"
    },
    {
      "kind": "const",
      "name": "columns",
      "identifier": 386,
      "description": "Number of columns on the screen",
      "fields": [
        {
          "name": "_",
          "unit": "#",
          "type": "u16",
          "storage": 2,
          "isSimpleType": true
        }
      ],
      "packFormat": "u16"
    },
    {
      "kind": "const",
      "name": "variant",
      "identifier": 263,
      "description": "Describes the type of matrix used.",
      "fields": [
        {
          "name": "_",
          "type": "Variant",
          "storage": 1
        }
      ],
      "optional": true,
      "identifierName": "variant",
      "packFormat": "u8"
    }
  ],
  "tags": [],
  "group": "Display"
}