diff --git a/src/converter.rs b/src/converter.rs
index 472ef0f..fbdf7f1 100644
--- a/src/converter.rs
+++ b/src/converter.rs
@@ -517,17 +517,22 @@ impl Field {
     /// Generate Field from Registers (piracy), guessing a lot of parameters.
     pub(crate) fn from_xml_register_dom(node: Node) -> Result<Self, DomConversionError> {
         let name = util::get_name(node)?;
-        let mask = node
-            .ancestors()
-            .filter_map(|node| util::get_type(node))
-            .next()
-            .transpose()?
-            .map_or_else(
-                || Err(DomConversionError::parameter_completion_error("type", node)),
-                |dtype| match dtype {
-                    crate::types::DataType::D32 => Ok(u32::MAX),
-                },
-            )?;
+        let mask = match node.attribute("mask") {
+            Some(mask) => mask
+                .parse_prefixed_u32()
+                .map_err(|e| DomConversionError::parse_prefixed_u32_error(e, "mask", node))?,
+            None => node
+                .ancestors()
+                .filter_map(|node| util::get_type(node))
+                .next()
+                .transpose()?
+                .map_or_else(
+                    || Err(DomConversionError::parameter_completion_error("type", node)),
+                    |dtype| match dtype {
+                        crate::types::DataType::D32 => Ok(u32::MAX),
+                    },
+                )?,
+        };
         if node.has_attribute("default") {
             return Err(DomConversionError::other_error(
                 "unsupported structure: register with @default without field",