diff --git a/schema/registers.json b/schema/registers.json
index 3787c9c..22901d3 100644
--- a/schema/registers.json
+++ b/schema/registers.json
@@ -113,9 +113,14 @@
                     "type": "integer"
                 },
                 "offset": {
-                    "description": "Specifies the payload array offset where this payload member is stored.",
+                    "description": "Specifies the payload array offset where this payload member is encoded.",
                     "type": "integer"
                 },
+                "length": {
+                    "description": "Specifies the number of elements in the payload array used to encode this payload member.",
+                    "type": "integer",
+                    "minimum": 1
+                },
                 "description": {
                     "description": "Specifies a summary description of the payload member.",
                     "type": "string"