diff --git a/.jshintrc b/.jshintrc
index a3ad17f..6f9bf81 100644
--- a/.jshintrc
+++ b/.jshintrc
@@ -19,7 +19,6 @@
   "immed": true,
   "browser": false,
   "es3": true,
-  "maxlen": 80,
   "nonbsp": true,
   "freeze": true,
   "node": true,
diff --git a/.travis.yml b/.travis.yml
index e843f40..30818d8 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,7 @@ before_install:
   - if [[ "$TASK" == "spellintian" ]]; then sudo add-apt-repository ppa:waja/trusty-backports -y; sudo apt-get update -qq; sudo apt-get install lintian -y; fi # Install a late enough lintian
 
 install:
-  - if [ "$TASK" = "codespell" ]; then npm install -g grunt-cli; fi
+  - if [ "$TASK" = "npm-test" ]; then npm install -g grunt-cli; fi
   - if [ "$TASK" = "npm-test" ]; then npm install; fi
   - if [ "$TASK" = "codespell" ]; then pip install urllib3[secure]; fi
   - if [ "$TASK" = "codespell" ]; then sudo pip install --upgrade git+https://github.com/codespell-project/codespell.git; fi
diff --git a/data/bitfields.json b/data/bitfields.json
index 67dd2b7..1a27f67 100644
--- a/data/bitfields.json
+++ b/data/bitfields.json
@@ -2,22 +2,18 @@
   "name": "PROXIED_DEVICES",
   "pid": 16,
   "version": 1,
-  "get_request": {
-    "fields": []
-  },
-  "get_response": {
-    "fields": [
-      {
-        "type": "bitfield",
-        "size": 8,
-        "bits": [
-          {
-            "index": 0,
-            "name": "foo"
-          }
-        ]
-      }
-    ]
-  },
-  "get_subdevice_range": 0
+  "get_request": [],
+  "get_response": [
+    {
+      "type": "bitField",
+      "size": 8,
+      "bits": [
+        {
+          "index": 0,
+          "name": "foo"
+        }
+      ]
+    }
+  ],
+  "get_subdevice_range": "root"
 }
diff --git a/data/device_info.json b/data/device_info.json
index 320f463..b514d35 100644
--- a/data/device_info.json
+++ b/data/device_info.json
@@ -2,38 +2,34 @@
   "name": "DEVICE_INFO",
   "pid": 96,
   "version": 1,
-  "get_request": {
-    "fields": []
-  },
-  "get_response": {
-    "fields": [
-      {"name": "protocol_major", "type": "uint8"},
-      {"name": "protocol_minor", "type": "uint8"},
-      {"name": "device_model", "type": "uint16"},
-      {"name": "product_category", "type": "uint16"},
-      {"name": "software_version", "type": "uint32"},
-      {
-        "name": "dmx_footprint",
-        "type": "uint16",
-        "ranges": [
-          {
-            "lower": 0,
-            "upper": 512
-          }
-        ],
-        "labels": [
-          {
-            "label": "No footprint",
-            "value": 65535
-          }
-        ]
-      },
-      {"name": "current_personality", "type": "uint8"},
-      {"name": "personality_count", "type": "uint8"},
-      {"name": "dmx_start_address", "type": "uint16"},
-      {"name": "sub_device_count", "type": "uint16"},
-      {"name": "sensor_count", "type": "uint8"}
-    ]
-  },
-  "get_subdevice_range": 2
+  "get_request": [],
+  "get_response": [
+    {"name": "protocol_major", "type": "uint8"},
+    {"name": "protocol_minor", "type": "uint8"},
+    {"name": "device_model", "type": "uint16"},
+    {"name": "product_category", "type": "uint16"},
+    {"name": "software_version", "type": "uint32"},
+    {
+      "name": "dmx_footprint",
+      "type": "uint16",
+      "ranges": [
+        {
+          "minimum": 0,
+          "maximum": 512
+        }
+      ],
+      "labels": [
+        {
+          "label": "No footprint",
+          "value": 65535
+        }
+      ]
+    },
+    {"name": "current_personality", "type": "uint8"},
+    {"name": "personality_count", "type": "uint8"},
+    {"name": "dmx_start_address", "type": "uint16"},
+    {"name": "sub_device_count", "type": "uint16"},
+    {"name": "sensor_count", "type": "uint8"}
+  ],
+  "get_subdevice_range": "root_or_any_subdevice"
 }
diff --git a/data/dmx_start_address.json b/data/dmx_start_address.json
index 5acf044..524c40f 100644
--- a/data/dmx_start_address.json
+++ b/data/dmx_start_address.json
@@ -2,52 +2,44 @@
   "name": "DMX_START_ADDRESS",
   "pid": 240,
   "version": 1,
-  "get_request": {
-    "fields": []
-  },
-  "get_response": {
-    "fields": [
-      {
-        "name": "start_address",
-        "type": "uint16",
-        "ranges": [
-          {
-            "lower": 0,
-            "upper": 512
-          }
-        ],
-        "labels": [
-          {
-            "label": "No footprint",
-            "value": 65535
-          }
-        ]
-      }
-    ]
-  },
-  "get_subdevice_range": 2,
-  "set_request": {
-    "fields": [
-      {
-        "name": "start_address",
-        "type": "uint16",
-        "ranges": [
-          {
-            "lower": 0,
-            "upper": 512
-          }
-        ],
-        "labels": [
-          {
-            "label": "No footprint",
-            "value": 65535
-          }
-        ]
-      }
-    ]
-  },
-  "set_response": {
-    "fields": []
-  },
-  "set_subdevice_range": 3
+  "get_request": [],
+  "get_response": [
+     {
+      "name": "start_address",
+      "type": "uint16",
+      "ranges": [
+        {
+          "minimum": 0,
+          "maximum": 512
+        }
+      ],
+      "labels": [
+        {
+          "label": "No footprint",
+          "value": 65535
+        }
+      ]
+    }
+  ],
+  "get_subdevice_range": "root_or_any_subdevice",
+  "set_request": [
+    {
+      "name": "start_address",
+      "type": "uint16",
+      "ranges": [
+        {
+          "minimum": 0,
+          "maximum": 512
+        }
+      ],
+      "labels": [
+        {
+          "label": "No footprint",
+          "value": 65535
+        }
+      ]
+    }
+  ],
+  "set_response": [],
+  "set_subdevice_range": "root_or_any_subdevice_or_broadcast"
 }
diff --git a/data/proxied_devices.json b/data/proxied_devices.json
index 768260d..ca04790 100644
--- a/data/proxied_devices.json
+++ b/data/proxied_devices.json
@@ -2,22 +2,16 @@
   "name": "PROXIED_DEVICES",
   "pid": 16,
   "version": 1,
-  "get_request": {
-    "fields": []
-  },
-  "get_response": {
-    "fields": [
-      {
-        "name": "devices",
-        "type": "group",
-        "fields": [
-          {
-            "name": "uid",
-            "type": "uid"
-          }
-        ]
+  "get_request": [],
+  "get_response": [
+    {
+      "name": "devices",
+      "type": "list",
+      "itemType": {
+          "name": "uid",
+          "type": "uid"
       }
-    ]
-  },
-  "get_subdevice_range": 2
+    }
+  ],
+  "get_subdevice_range": "root_or_any_subdevice"
 }
diff --git a/package.json b/package.json
index 7c531b2..81d15b2 100644
--- a/package.json
+++ b/package.json
@@ -6,10 +6,10 @@
   "dependencies": {
     "grunt": "^1.0.0",
     "grunt-contrib-jshint": "^0.12.0",
-    "grunt-jsonschema-ajv": "^0.1.0",
+    "grunt-jsonschema-ajv": "github:peternewman/grunt-jsonschema-ajv#travis",
     "ajv": "^6.10.2"
   },
   "scripts": {
-    "test": "grunt --verbose --stack"
+    "test": "grunt --verbose --debug --stack"
   }
 }
diff --git a/schema.json b/schema.json
index ecc5cd3..c18d93f 100644
--- a/schema.json
+++ b/schema.json
@@ -1,255 +1,252 @@
 {
-  "$schema": "http://json-schema.org/draft-04/schema#",
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Parameter Metadata Language Schema, Informative",
+  "description": "The (informative) schema for the Parameter Metadata Language from E1.37-5, Section 5. This schema is subject to change.",
   "definitions": {
-    "bitfield": {
+    "bitType": {
+      "description": "Describes the meaning of one bit in a bit field.",
       "type": "object",
       "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
         "index": {
           "type": "integer",
           "minimum": 0
-        },
-        "name": {
-          "$ref": "#/definitions/name"
         }
       },
-      "required": ["index", "name"]
+      "required": [ "name", "index" ]
+    },
+    "bitFieldType": {
+      "description": "A bit field, a collection of 'bit' items.",
+      "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": { "const": "bitField" },
+        "bits": {
+          "type": "array",
+          "items": { "$ref": "#/definitions/bitType" },
+          "uniqueItems": true
+        },
+        "size": {
+          "type": "integer",
+          "multipleOf": 8
+        } 
+      },
+      "required": [ "type", "bits" ]
+    },
+    "commandType": {
+      "description": "Represents an RDM command, a collection of 'field' items, each a simple or compound type.",
+      "type": "array",
+      "items": { "$ref": "#/definitions/oneOfTypes" },
+      "uniqueItems": true
     },
-    "command": {
+    "compoundType": {
+      "description": "Defines a compound type, a type used to combine other types. This is useful for including in lists.",
       "type": "object",
       "properties": {
-        "fields": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": { "const": "compound" },
+        "subtypes": {
           "type": "array",
           "items": {
-            "$ref": "#/definitions/field"
+            "$ref": "#/definitions/oneOfTypes"
           }
         }
       },
-      "required": ["fields"]
+      "required": [ "type", "subtypes" ]
     },
-    "field": {
-      "type": "object",
-      "oneOf": [
-        {
-          "properties": {
-            "type": {
-              "enum": ["bitfield"]
-            },
-            "bits": {
-              "type": "array",
-              "items": {
-                "$ref": "#/definitions/bitfield"
-              }
-            },
-            "size": {
-              "type": "integer",
-              "multipleOf": 8
-            }
-          },
-          "required": ["bits", "type", "size"]
-        },
-        {
-          "properties": {
-            "type": {
-              "enum": ["bool"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            }
-          },
-          "required": ["name", "type"]
-        },
-        {
-          "properties": {
-            "type": {
-              "enum": ["int8", "int16", "int32", "int64",
-                       "uint8", "uint16", "uint32", "uint64"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            },
-            "labels": {
-              "type": "array",
-              "items": {
-                "$ref": "#/definitions/label"
-              }
-            },
-            "prefix": {
-              "type": "integer",
-              "maximum": 255,
-              "minimum": 0
-            },
-            "ranges": {
-              "type": "array",
-              "items": {
-                "$ref": "#/definitions/range"
-              }
-            },
-            "unit": {
-              "type": "integer",
-              "maximum": 255,
-              "minimum": 0
-            }
-          },
-          "required": ["name", "type"]
-        },
-        {
-          "properties": {
-            "type": {
-              "enum": ["string"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            },
-            "max_size": {
-              "type": "integer",
-              "minimum": 0,
-              "exclusiveMinimum": true
-            },
-            "min_size": {
-              "type": "integer",
-              "minimum": 0
-            }
-          },
-          "required": ["name", "type"]
+    "integerType": {
+      "description": "A signed or unsigned integer, can have an optional prefix, unit, and range.",
+      "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": {
+          "enum": [
+            "int8",
+            "int16",
+            "int32",
+            "int64",
+            "uint8",
+            "uint16",
+            "uint32",
+            "uint64"
+          ]
         },
-        {
-          "properties": {
-            "type": {
-              "enum": ["ipv4"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            }
-          },
-          "required": ["name", "type"]
+        "labels": {
+          "description": "A list of labels that name special values.",
+          "type": "array",
+          "items": { "$ref": "#/definitions/labeledIntegerType" },
+          "uniqueItems": true
         },
-        {
-          "properties": {
-            "type": {
-              "enum": ["mac"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            }
-          },
-          "required": ["name", "type"]
+        "prefix": {
+          "description": "The unit prefix, defined in Table A-14 of E1.20.",
+          "type": "integer",
+          "minimum": 0,
+          "maximum": 255
         },
-        {
-          "properties": {
-            "type": {
-              "enum": ["uid"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            }
-          },
-          "required": ["name", "type"]
+        "ranges": {
+          "description": "A list of possible ranges for the value. The complete range is the union of all the ranges and labels.",
+          "type": "array",
+          "items": { "$ref": "#/definitions/rangeType" },
+          "uniqueItems": true
         },
-        {
-          "properties": {
-            "type": {
-              "enum": ["group"]
-            },
-            "name": {
-              "$ref": "#/definitions/name"
-            },
-            "fields": {
-              "type": "array",
-              "items": {
-                "$ref": "#/definitions/field"
-              }
-            },
-            "max_size": {
-              "type": "integer",
-              "minimum": 0,
-              "exclusiveMinimum": true
-            },
-            "min_size": {
-              "type": "integer",
-              "minimum": 0
-            }
-          },
-          "required": ["name", "fields", "type"]
+        "unit": {
+          "description": "The unit type, defined in Table A-13 of E1.20.",
+          "type": "integer",
+          "minimum": 0,
+          "maximum": 255
         }
-      ]
+      },
+      "required": [ "type" ]
+    },
+    "labeledIntegerType": {
+      "description": "Associates a name to an integer value.",
+      "type": "object",
+      "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "value": { "type": "integer" }
+      },
+      "required": [ "value" ]
     },
-    "label": {
+    "listType": {
+      "description": "A list of objects all having the same type.",
       "type": "object",
       "properties": {
-        "label": {
-          "minLength": 1,
-          "type": "string"
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": { "const": "list" },
+        "itemType": {
+          "$ref": "#/definitions/oneOfTypes"
         },
-        "value": {
+        "minItems": {
+          "description": "The minimum list size.",
+          "type": "integer",
+          "minimum": 0
+        },
+        "maxItems": {
+          "description": "The maximum list size.",
           "type": "integer",
-          "maximum": 4294967295,
           "minimum": 0
         }
       },
-      "required": ["label", "value"]
+      "required": [ "type", "itemType" ]
     },
-    "name": {
+    "nameType": {
+      "description": "A name is a string having a length of at least 1.",
       "type": "string",
       "minLength": 1
     },
-    "range": {
+    "oneOfTypes": {
+      "description": "One of any of the types. This provides a single location to keep the list.",
+      "oneOf": [
+        { "$ref": "#/definitions/bitFieldType" },
+        { "$ref": "#/definitions/compoundType" },
+        { "$ref": "#/definitions/integerType" },
+        { "$ref": "#/definitions/listType" },
+        { "$ref": "#/definitions/pdEnvelopeType" },
+        { "$ref": "#/definitions/simpleType" },
+        { "$ref": "#/definitions/stringType" }
+      ]
+    },
+    "subdeviceType": {
+      "description": "A subdevice type. One of the root device (e.g. value 0), the root or all subdevices or the broadcast subdevice, the root or any subdevice, or just any subdevice.",
+      "type" : "string",
+      "enum": [
+            "root",
+            "root_or_any_subdevice_or_broadcast",
+            "root_or_any_subdevice",
+            "any_subdevice"
+          ]
+    },
+    "pdEnvelopeType": {
+      "description": "Contains a length/data pair for one Parameter Data item, where the length is an unsigned 8-bit value and the data has 'length' bytes. This exists to provide a schema definition for the 'envelope' of a PDL/PD pair.",
+      "type": "object",
+      "properties": {
+        "type": { "const": "pdEnvelope" },
+        "length": {
+          "description": "The data length can be optionally specified.",
+          "type": "integer",
+          "minimum": 0
+        }
+      },
+      "required": [ "type" ]
+    },
+    "rangeType": {
+      "description": "Defines an inclusive range of numbers.",
       "type": "object",
       "properties": {
-        "lower": {
+        "minimum": {
+          "description": "The lower bound, inclusive.",
           "type": "integer"
         },
-        "upper": {
+        "maximum": {
+          "description": "The upper bound, inclusive.",
           "type": "integer"
         }
       },
-      "required": ["lower", "upper"]
+      "required": [ "minimum", "maximum" ]
+    },
+    "simpleType": {
+      "description": "Simple type that has no fields other than a name and type.",
+      "type": "object",
+      "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": {
+          "enum": [
+            "bool",
+            "hostname",
+            "ipv4",
+            "ipv6",
+            "mac",
+            "uid",
+            "url"
+          ]
+        }
+      },
+      "required": [ "type" ]
+    },
+    "stringType": {
+      "description": "A string having a possibly bounded size.",
+      "properties": {
+        "name": { "$ref": "#/definitions/nameType" },
+        "type": { "const": "string" },
+        "minLength": {
+          "description": "The minimum string length.",
+          "type": "integer",
+          "minimum": 0
+        },
+        "maxLength": {
+          "description": "The maximum string length.",
+          "type": "integer",
+          "minimum": 0
+        }
+      },
+      "required": [ "type" ]
     }
   },
   "type": "object",
   "properties": {
-    "get_request": {
-      "$ref": "#/definitions/command"
-    },
-    "get_response": {
-      "$ref": "#/definitions/command"
-    },
-    "get_subdevice_range": {
-      "maximum": 3,
-      "minimum": 0,
-      "type": "integer"
-    },
-    "name": {
-      "minLength": 1,
-      "type": "string"
-    },
+    "name": { "$ref": "#/definitions/nameType" },
     "pid": {
-      "maximum": 65535,
-      "minimum": 0,
-      "type": "integer"
-    },
-    "set_request": {
-      "$ref": "#/definitions/command"
-    },
-    "set_response": {
-      "$ref": "#/definitions/command"
-    },
-    "set_subdevice_range": {
-      "maximum": 3,
+      "type": "integer",
       "minimum": 0,
-      "type": "integer"
+      "maximum": 65535
     },
     "version": {
-      "minimum": 0,
-      "type": "integer"
-    }
+      "type": "integer",
+      "minimum": 1,
+      "maximum": 65535
+    },
+    "get_request": { "$ref": "#/definitions/commandType" },
+    "get_response": { "$ref": "#/definitions/commandType" },
+    "get_subdevice_range" : { "$ref": "#/definitions/subdeviceType" },
+    "set_request": { "$ref": "#/definitions/commandType" },
+    "set_response": { "$ref": "#/definitions/commandType" },
+    "set_subdevice_range" : { "$ref": "#/definitions/subdeviceType" }
   },
-  "required": ["name", "pid", "version"],
+  "required": [ "name", "pid", "version" ],
   "dependencies": {
-    "get_request": ["get_response", "get_subdevice_range"],
-    "get_response": ["get_request", "get_subdevice_range"],
-    "get_subdevice_range": ["get_request", "get_response"],
-    "set_request": ["set_response", "set_subdevice_range"],
-    "set_response": ["set_request", "set_subdevice_range"],
-    "set_subdevice_range": ["set_request", "set_response"]
+    "get_request": [ "get_response" ],
+    "get_response": [ "get_request" ],
+    "get_subdevice_range" : [ "get_request", "get_response" ],   
+    "set_request": [ "set_response" ],
+    "set_response": [ "set_request" ],
+    "set_subdevice_range" : [ "set_request", "set_response" ]
   }
 }